diff --git a/lambdas/core-notifier-lambda/src/__tests__/constants.ts b/lambdas/core-notifier-lambda/src/__tests__/constants.ts
index e81c888a0..c4edd3cca 100644
--- a/lambdas/core-notifier-lambda/src/__tests__/constants.ts
+++ b/lambdas/core-notifier-lambda/src/__tests__/constants.ts
@@ -60,8 +60,8 @@ export const mockResponse: SingleMessageResponse = {
 
 export const validPdmEvent: PDMResourceAvailable = {
   id: 'event-id-123',
-  source:
-    '/nhs/england/notify/development/dev-12345/data-plane/digitalletters/pdm',
+  plane: 'data',
+  source: '/nhs/england/notify/development/dev-12345/digitalletters/pdm',
   specversion: '1.0',
   type: 'uk.nhs.notify.digital.letters.pdm.resource.available.v1',
   time: '2025-12-15T10:00:00Z',
diff --git a/lambdas/file-scanner-lambda/src/__tests__/apis/sqs-handler.test.ts b/lambdas/file-scanner-lambda/src/__tests__/apis/sqs-handler.test.ts
index 0f961678e..4c7e22c9c 100644
--- a/lambdas/file-scanner-lambda/src/__tests__/apis/sqs-handler.test.ts
+++ b/lambdas/file-scanner-lambda/src/__tests__/apis/sqs-handler.test.ts
@@ -42,8 +42,8 @@ const createValidItemDequeuedBody = (
     detail: {
       specversion: '1.0',
       id: `event-${messageReference}`,
-      source:
-        '/nhs/england/notify/development/primary/data-plane/digitalletters/queue',
+      plane: 'data',
+      source: '/nhs/england/notify/development/primary/digitalletters/queue',
       subject: `message/${messageReference}`,
       type: 'uk.nhs.notify.digital.letters.queue.item.dequeued.v1',
       time: '2026-01-19T12:00:00Z',
@@ -319,7 +319,7 @@ describe('SQS Handler', () => {
               specversion: '1.0',
               id: 'event-001',
               source:
-                '/nhs/england/notify/development/primary/data-plane/digitalletters/queue',
+                '/nhs/england/notify/development/primary/digitalletters/queue',
               type: 'uk.nhs.notify.wrong.event.type.v1',
               time: '2026-01-19T12:00:00Z',
               data: {
@@ -386,7 +386,7 @@ describe('SQS Handler', () => {
               specversion: '1.0',
               id: 'event-001',
               source:
-                '/nhs/england/notify/development/primary/data-plane/digitalletters/queue',
+                '/nhs/england/notify/development/primary/digitalletters/queue',
               type: 'uk.nhs.notify.digital.letters.queue.item.dequeued.v1',
               time: '2026-01-19T12:00:00Z',
               data: {
diff --git a/lambdas/mesh-acknowledge/mesh_acknowledge/__tests__/fixtures.py b/lambdas/mesh-acknowledge/mesh_acknowledge/__tests__/fixtures.py
index c21eb130f..96e7d10b0 100644
--- a/lambdas/mesh-acknowledge/mesh_acknowledge/__tests__/fixtures.py
+++ b/lambdas/mesh-acknowledge/mesh_acknowledge/__tests__/fixtures.py
@@ -9,7 +9,7 @@ def create_downloaded_event_dict(event_id: str) -> Dict[str, str | int | Dict[st
         "specversion": "1.0",
         "source": (
             "/nhs/england/notify/production/primary/"
-            'data-plane/digitalletters/mesh'
+            'digitalletters/mesh'
         ),
         "subject": (
             'customer/920fca11-596a-4eca-9c47-99f624614658/'
diff --git a/lambdas/mesh-acknowledge/mesh_acknowledge/__tests__/test_events.py b/lambdas/mesh-acknowledge/mesh_acknowledge/__tests__/test_events.py
index cbfa2de87..ec1d50101 100644
--- a/lambdas/mesh-acknowledge/mesh_acknowledge/__tests__/test_events.py
+++ b/lambdas/mesh-acknowledge/mesh_acknowledge/__tests__/test_events.py
@@ -66,7 +66,7 @@ def create_invalid_sqs_record(event_id: str) -> Dict[str, str]:
             'detail': {
                 'id': event_id,
                 'specversion': '1.0',
-                'source': '/nhs/england/notify/production/primary/data-plane/digitalletters/mesh',
+                'source': '/nhs/england/notify/production/primary/digitalletters/mesh',
                 'subject': (
                     'customer/920fca11-596a-4eca-9c47-99f624614658/recipient/'
                     '769acdd4-6a47-496f-999f-76a6fd2c3959'
diff --git a/lambdas/mesh-download/mesh_download/__tests__/test_processor.py b/lambdas/mesh-download/mesh_download/__tests__/test_processor.py
index ecfc997be..b7ff2089f 100644
--- a/lambdas/mesh-download/mesh_download/__tests__/test_processor.py
+++ b/lambdas/mesh-download/mesh_download/__tests__/test_processor.py
@@ -38,7 +38,7 @@ def create_valid_cloud_event():
     return {
         'id': str(uuid4()),
         'specversion': '1.0',
-        'source': '/nhs/england/notify/development/primary/data-plane/digitalletters/mesh',
+        'source': '/nhs/england/notify/development/primary/digitalletters/mesh',
         'subject': 'customer/00000000-0000-0000-0000-000000000000/recipient/00000000-0000-0000-0000-000000000000',
         'type': 'uk.nhs.notify.digital.letters.mesh.inbox.message.received.v1',
         'time': '2023-01-01T12:00:00Z',
@@ -159,7 +159,7 @@ def test_process_sqs_message_success(self, mock_datetime):
 
         # Verify CloudEvent envelope fields
         assert published_event['type'] == 'uk.nhs.notify.digital.letters.mesh.inbox.message.downloaded.v1'
-        assert published_event['source'] == '/nhs/england/notify/development/primary/data-plane/digitalletters/mesh'
+        assert published_event['source'] == '/nhs/england/notify/development/primary/digitalletters/mesh'
         assert published_event['subject'] == 'customer/00000000-0000-0000-0000-000000000000/recipient/00000000-0000-0000-0000-000000000000'
         assert published_event['time'] == '2025-11-19T15:30:45+00:00'
         assert 'id' in published_event
diff --git a/lambdas/mesh-poll/mesh_poll/processor.py b/lambdas/mesh-poll/mesh_poll/processor.py
index 79ff65273..ccbf77053 100644
--- a/lambdas/mesh-poll/mesh_poll/processor.py
+++ b/lambdas/mesh-poll/mesh_poll/processor.py
@@ -30,9 +30,8 @@ def __init__(self, **kwargs):
 
         environment = 'development'
         deployment = 'primary'
-        plane = 'data-plane'
         self.__cloud_event_source = (
-            f'/nhs/england/notify/{environment}/{deployment}/{plane}/'
+            f'/nhs/england/notify/{environment}/{deployment}/'
             'digitalletters/mesh'
         )
 
diff --git a/lambdas/move-scanned-files-lambda/src/__tests__/domain/mapper.test.ts b/lambdas/move-scanned-files-lambda/src/__tests__/domain/mapper.test.ts
index 40826e9f6..28cd3be0f 100644
--- a/lambdas/move-scanned-files-lambda/src/__tests__/domain/mapper.test.ts
+++ b/lambdas/move-scanned-files-lambda/src/__tests__/domain/mapper.test.ts
@@ -43,8 +43,8 @@ describe('mapper', () => {
         specversion: '1.0',
         id: 'mocked-uuid-12345',
         subject: `customer/${senderId}/recipient/${messageReference}`,
-        source:
-          '/nhs/england/notify/production/primary/data-plane/digitalletters/print',
+        source: '/nhs/england/notify/production/primary/digitalletters/print',
+        plane: 'data',
         traceparent: '00-0af7651916cd43dd8448eb211c80319c-b7ad6b7169203331-01',
         type: 'uk.nhs.notify.digital.letters.print.file.safe.v1',
         time: '2024-01-15T10:30:00.000Z',
@@ -99,8 +99,8 @@ describe('mapper', () => {
         specversion: '1.0',
         id: 'mocked-uuid-12345',
         subject: `customer/${senderId}/recipient/${messageReference}`,
-        source:
-          '/nhs/england/notify/production/primary/data-plane/digitalletters/print',
+        plane: 'data',
+        source: '/nhs/england/notify/production/primary/digitalletters/print',
         traceparent: '00-0af7651916cd43dd8448eb211c80319c-b7ad6b7169203331-01',
         type: 'uk.nhs.notify.digital.letters.print.file.quarantined.v1',
         time: '2024-01-15T10:30:00.000Z',
diff --git a/lambdas/move-scanned-files-lambda/src/domain/mapper.ts b/lambdas/move-scanned-files-lambda/src/domain/mapper.ts
index c42208a04..0e9e66527 100644
--- a/lambdas/move-scanned-files-lambda/src/domain/mapper.ts
+++ b/lambdas/move-scanned-files-lambda/src/domain/mapper.ts
@@ -11,8 +11,8 @@ export function createFileSafeEvent(
     specversion: '1.0',
     id: randomUUID(),
     subject: `customer/${senderId}/recipient/${messageReference}`,
-    source:
-      '/nhs/england/notify/production/primary/data-plane/digitalletters/print', // Note CCM-13892.
+    plane: 'data',
+    source: '/nhs/england/notify/production/primary/digitalletters/print', // Note CCM-13892.
     traceparent: '00-0af7651916cd43dd8448eb211c80319c-b7ad6b7169203331-01', // Note CCM-14255.
     type: 'uk.nhs.notify.digital.letters.print.file.safe.v1',
     time: new Date().toISOString(),
@@ -37,8 +37,8 @@ export function createFileQuarantinedEvent(
     specversion: '1.0',
     id: randomUUID(),
     subject: `customer/${senderId}/recipient/${messageReference}`,
-    source:
-      '/nhs/england/notify/production/primary/data-plane/digitalletters/print', // Note CCM-13892.
+    plane: 'data',
+    source: '/nhs/england/notify/production/primary/digitalletters/print', // Note CCM-13892.
     traceparent: '00-0af7651916cd43dd8448eb211c80319c-b7ad6b7169203331-01', // Note CCM-14255.
     type: 'uk.nhs.notify.digital.letters.print.file.quarantined.v1',
     time: new Date().toISOString(),
diff --git a/lambdas/pdm-poll-lambda/src/__tests__/test-data.ts b/lambdas/pdm-poll-lambda/src/__tests__/test-data.ts
index 72698e3e7..a6631eabc 100644
--- a/lambdas/pdm-poll-lambda/src/__tests__/test-data.ts
+++ b/lambdas/pdm-poll-lambda/src/__tests__/test-data.ts
@@ -7,10 +7,10 @@ import {
 const baseEvent = {
   id: '550e8400-e29b-41d4-a716-446655440001',
   specversion: '1.0',
-  source:
-    '/nhs/england/notify/production/primary/data-plane/digitalletters/pdm',
+  source: '/nhs/england/notify/production/primary/digitalletters/pdm',
   subject:
     'customer/920fca11-596a-4eca-9c47-99f624614658/recipient/769acdd4-6a47-496f-999f-76a6fd2c3959',
+  plane: 'data',
   type: 'uk.nhs.notify.digital.letters.pdm.resource.submitted.v1',
   time: '2023-06-20T12:00:00Z',
   recordedtime: '2023-06-20T12:00:00.250Z',
diff --git a/lambdas/pdm-uploader-lambda/src/__tests__/data.ts b/lambdas/pdm-uploader-lambda/src/__tests__/data.ts
index bc8bef9dc..0e1b41992 100644
--- a/lambdas/pdm-uploader-lambda/src/__tests__/data.ts
+++ b/lambdas/pdm-uploader-lambda/src/__tests__/data.ts
@@ -3,8 +3,8 @@ import { MESHInboxMessageDownloaded } from 'digital-letters-events';
 export const mockEvent: MESHInboxMessageDownloaded = {
   id: 'a449d419-e683-4ab4-9291-a0451b5cef8e',
   specversion: '1.0',
-  source:
-    '/nhs/england/notify/production/primary/data-plane/digitalletters/mesh',
+  source: '/nhs/england/notify/production/primary/digitalletters/mesh',
+  plane: 'data',
   subject:
     'customer/920fca11-596a-4eca-9c47-99f624614658/recipient/769acdd4-6a47-496f-999f-76a6fd2c3959',
   type: 'uk.nhs.notify.digital.letters.mesh.inbox.message.downloaded.v1',
diff --git a/lambdas/print-analyser/src/__tests__/apis/sqs-handler.test.ts b/lambdas/print-analyser/src/__tests__/apis/sqs-handler.test.ts
index 800803e40..c90372cc7 100644
--- a/lambdas/print-analyser/src/__tests__/apis/sqs-handler.test.ts
+++ b/lambdas/print-analyser/src/__tests__/apis/sqs-handler.test.ts
@@ -58,7 +58,7 @@ describe('SQS Handler', () => {
               'https://notify.nhs.uk/cloudevents/schemas/digital-letters/2025-10-draft/data/digital-letters-print-pdf-analysed-data.schema.json',
             type: 'uk.nhs.notify.digital.letters.print.pdf.analysed.v1',
             source:
-              '/nhs/england/notify/production/primary/data-plane/digitalletters/print',
+              '/nhs/england/notify/production/primary/digitalletters/print',
             data: {
               senderId: fileSafeEvent.data.senderId,
               messageReference: fileSafeEvent.data.messageReference,
diff --git a/lambdas/print-analyser/src/__tests__/test-data.ts b/lambdas/print-analyser/src/__tests__/test-data.ts
index d03caaade..b5a05d363 100644
--- a/lambdas/print-analyser/src/__tests__/test-data.ts
+++ b/lambdas/print-analyser/src/__tests__/test-data.ts
@@ -6,8 +6,8 @@ import { FileSafe } from 'digital-letters-events';
 export const fileSafeEvent: FileSafe = {
   id: '550e8400-e29b-41d4-a716-446655440001',
   specversion: '1.0',
-  source:
-    '/nhs/england/notify/production/primary/data-plane/digitalletters/print',
+  source: '/nhs/england/notify/production/primary/digitalletters/print',
+  plane: 'data',
   subject:
     'letter-origin/digital-letters/letter/f47ac10b-58cc-4372-a567-0e02b2c3d479',
   type: 'uk.nhs.notify.digital.letters.print.file.safe.v1',
diff --git a/lambdas/print-analyser/src/apis/sqs-handler.ts b/lambdas/print-analyser/src/apis/sqs-handler.ts
index 5299a2645..c1a06db82 100644
--- a/lambdas/print-analyser/src/apis/sqs-handler.ts
+++ b/lambdas/print-analyser/src/apis/sqs-handler.ts
@@ -69,8 +69,7 @@ function generateUpdatedEvent(event: FileSafe, pdfInfo: PdfInfo): PDFAnalysed {
       'https://notify.nhs.uk/cloudevents/schemas/digital-letters/2025-10-draft/data/digital-letters-print-pdf-analysed-data.schema.json',
     type: 'uk.nhs.notify.digital.letters.print.pdf.analysed.v1',
     // NOTE: CCM-13892 Generate event digital letters source property from scratch
-    source:
-      '/nhs/england/notify/production/primary/data-plane/digitalletters/print',
+    source: '/nhs/england/notify/production/primary/digitalletters/print',
     data: {
       senderId,
       messageReference,
diff --git a/lambdas/print-sender-lambda/src/__tests__/apis/sqs-trigger-lambda.test.ts b/lambdas/print-sender-lambda/src/__tests__/apis/sqs-trigger-lambda.test.ts
index c0d17cd8a..c4a55bad7 100644
--- a/lambdas/print-sender-lambda/src/__tests__/apis/sqs-trigger-lambda.test.ts
+++ b/lambdas/print-sender-lambda/src/__tests__/apis/sqs-trigger-lambda.test.ts
@@ -28,8 +28,8 @@ const createValidEvent = (overrides = {}): PDFAnalysed => ({
   type: 'uk.nhs.notify.digital.letters.print.pdf.analysed.v1',
   dataschema:
     'https://notify.nhs.uk/cloudevents/schemas/digital-letters/2025-10-draft/data/digital-letters-print-pdf-analysed-data.schema.json',
-  source:
-    '/nhs/england/notify/production/primary/data-plane/digitalletters/print',
+  plane: 'data',
+  source: '/nhs/england/notify/production/primary/digitalletters/print',
   specversion: '1.0',
   traceparent: '00-0af7651916cd43dd8448eb211c80319c-b7ad6b7169203331-01',
   severitynumber: 2,
diff --git a/lambdas/print-status-handler/src/__tests__/apis/sqs-handler.test.ts b/lambdas/print-status-handler/src/__tests__/apis/sqs-handler.test.ts
index bb6df0531..f0e02f45d 100644
--- a/lambdas/print-status-handler/src/__tests__/apis/sqs-handler.test.ts
+++ b/lambdas/print-status-handler/src/__tests__/apis/sqs-handler.test.ts
@@ -45,7 +45,7 @@ describe('SQS Handler', () => {
               'https://notify.nhs.uk/cloudevents/schemas/digital-letters/2025-10-draft/data/digital-letters-print-letter-transitioned-data.schema.json',
             type: 'uk.nhs.notify.digital.letters.print.letter.transitioned.v1',
             source:
-              '/nhs/england/notify/production/primary/data-plane/digitalletters/print',
+              '/nhs/england/notify/production/primary/digitalletters/print',
             data: {
               senderId: acceptedLetterEvent.data.origin.subject.split('/')[1],
               messageReference:
@@ -82,7 +82,7 @@ describe('SQS Handler', () => {
               'https://notify.nhs.uk/cloudevents/schemas/digital-letters/2025-10-draft/data/digital-letters-print-letter-transitioned-data.schema.json',
             type: 'uk.nhs.notify.digital.letters.print.letter.transitioned.v1',
             source:
-              '/nhs/england/notify/production/primary/data-plane/digitalletters/print',
+              '/nhs/england/notify/production/primary/digitalletters/print',
             data: {
               senderId: failedLetterEvent.data.origin.subject.split('/')[1],
               messageReference:
diff --git a/lambdas/print-status-handler/src/apis/sqs-handler.ts b/lambdas/print-status-handler/src/apis/sqs-handler.ts
index d75d7a678..0600977e6 100644
--- a/lambdas/print-status-handler/src/apis/sqs-handler.ts
+++ b/lambdas/print-status-handler/src/apis/sqs-handler.ts
@@ -106,8 +106,7 @@ function generateUpdatedEvent(event: LetterEvent): PrintLetterTransitioned {
       'https://notify.nhs.uk/cloudevents/schemas/digital-letters/2025-10-draft/data/digital-letters-print-letter-transitioned-data.schema.json',
     type: 'uk.nhs.notify.digital.letters.print.letter.transitioned.v1',
     // NOTE: CCM-13892 Generate event digital letters source property from scratch
-    source:
-      '/nhs/england/notify/production/primary/data-plane/digitalletters/print',
+    source: '/nhs/england/notify/production/primary/digitalletters/print',
     data: {
       senderId,
       messageReference,
diff --git a/lambdas/report-event-transformer/src/__tests__/test-data.ts b/lambdas/report-event-transformer/src/__tests__/test-data.ts
index f017e165b..af2e66fba 100644
--- a/lambdas/report-event-transformer/src/__tests__/test-data.ts
+++ b/lambdas/report-event-transformer/src/__tests__/test-data.ts
@@ -4,8 +4,7 @@ import { DigitalLettersEvent } from 'types/events';
 export const digitalLettersEvent = {
   id: '550e8400-e29b-41d4-a716-446655440001',
   specversion: '1.0',
-  source:
-    '/nhs/england/notify/production/primary/data-plane/digitalletters/pdm',
+  source: '/nhs/england/notify/production/primary/digitalletters/pdm',
   subject:
     'customer/920fca11-596a-4eca-9c47-99f624614658/recipient/769acdd4-6a47-496f-999f-76a6fd2c3959',
   type: 'uk.nhs.notify.digital.letters.pdm.resource.submitted.v1',
diff --git a/lambdas/report-generator/src/__tests__/apis/sqs-trigger-lambda.test.ts b/lambdas/report-generator/src/__tests__/apis/sqs-trigger-lambda.test.ts
index 7cb243548..5ec84bc4f 100644
--- a/lambdas/report-generator/src/__tests__/apis/sqs-trigger-lambda.test.ts
+++ b/lambdas/report-generator/src/__tests__/apis/sqs-trigger-lambda.test.ts
@@ -23,7 +23,8 @@ const createMockSQSRecord = (
       id: event.id || mockUuid,
       source:
         event.source ||
-        '/nhs/england/notify/development/primary/data-plane/digitalletters/reporting',
+        '/nhs/england/notify/development/primary/digitalletters/reporting',
+      plane: 'data',
       specversion: event.specversion || '1.0',
       type:
         event.type ||
diff --git a/lambdas/report-scheduler/src/__tests__/apis/scheduled-event-handler.test.ts b/lambdas/report-scheduler/src/__tests__/apis/scheduled-event-handler.test.ts
index fe8cd4fa0..753bad75c 100644
--- a/lambdas/report-scheduler/src/__tests__/apis/scheduled-event-handler.test.ts
+++ b/lambdas/report-scheduler/src/__tests__/apis/scheduled-event-handler.test.ts
@@ -98,8 +98,9 @@ describe('scheduled-event-handler', () => {
       expect(event.data.reportDate).toBe('2024-01-14');
       expect(event.specversion).toBe('1.0');
       expect(event.id).toBeDefined();
+      expect(event.plane).toBe('data');
       expect(event.source).toBe(
-        '/nhs/england/notify/production/primary/data-plane/digitalletters/reporting',
+        '/nhs/england/notify/production/primary/digitalletters/reporting',
       );
       expect(event.subject).toBe('customer/test-sender-123');
       expect(event.type).toBe(
diff --git a/lambdas/report-scheduler/src/apis/scheduled-event-handler.ts b/lambdas/report-scheduler/src/apis/scheduled-event-handler.ts
index 6e85a0dc2..334ee6074 100644
--- a/lambdas/report-scheduler/src/apis/scheduled-event-handler.ts
+++ b/lambdas/report-scheduler/src/apis/scheduled-event-handler.ts
@@ -27,8 +27,9 @@ export const createHandler = ({
         },
         specversion: '1.0',
         id: randomUUID(),
+        plane: 'data',
         source:
-          '/nhs/england/notify/production/primary/data-plane/digitalletters/reporting', // CCM-13892
+          '/nhs/england/notify/production/primary/digitalletters/reporting', // CCM-13892
         subject: `customer/${sender.senderId}`,
         type: 'uk.nhs.notify.digital.letters.reporting.generate.report.v1',
         time: new Date().toISOString(),
diff --git a/lambdas/report-sender/report_sender/__tests__/test_report_sender_processor.py b/lambdas/report-sender/report_sender/__tests__/test_report_sender_processor.py
index 339f72adb..ccbdbda57 100644
--- a/lambdas/report-sender/report_sender/__tests__/test_report_sender_processor.py
+++ b/lambdas/report-sender/report_sender/__tests__/test_report_sender_processor.py
@@ -92,7 +92,7 @@ def create_valid_sqs_record(sender_id=SENDER_ID, report_uri=REPORT_URI):
             'detail': {
                 'id': '6f1c2a53-3d54-4a0a-9a0b-0e9ae2d4c111',
                 'specversion': '1.0',
-                'source': '/nhs/england/notify/development/primary/data-plane/digitalletters/reporting',
+                'source': '/nhs/england/notify/development/primary/digitalletters/reporting',
                 'subject': 'customer/920fca11-596a-4eca-9c47-99f624614658',
                 'type': 'uk.nhs.notify.digital.letters.reporting.report.generated.v1',
                 'time': '2026-02-03T10:00:00Z',
diff --git a/lambdas/report-sender/report_sender/report_sender_processor.py b/lambdas/report-sender/report_sender/report_sender_processor.py
index daddf28c2..68204e6c8 100644
--- a/lambdas/report-sender/report_sender/report_sender_processor.py
+++ b/lambdas/report-sender/report_sender/report_sender_processor.py
@@ -24,8 +24,7 @@ def __init__(self, **kwargs):
 
         environment = 'development'
         deployment = 'primary'
-        plane = 'data-plane'
-        self.__cloud_event_source = f'/nhs/england/notify/{environment}/{deployment}/{plane}/digitalletters/reporting'
+        self.__cloud_event_source = f'/nhs/england/notify/{environment}/{deployment}/digitalletters/reporting'
 
     def _parse_and_validate_event(self, sqs_record) -> ReportGenerated:
         """Extract report generated data from SQS record"""
diff --git a/lambdas/ttl-create-lambda/src/__tests__/apis/sqs-trigger-lambda.test.ts b/lambdas/ttl-create-lambda/src/__tests__/apis/sqs-trigger-lambda.test.ts
index f31d41cc2..c795001dd 100644
--- a/lambdas/ttl-create-lambda/src/__tests__/apis/sqs-trigger-lambda.test.ts
+++ b/lambdas/ttl-create-lambda/src/__tests__/apis/sqs-trigger-lambda.test.ts
@@ -26,8 +26,7 @@ describe('createHandler', () => {
   const itemEnqueuedEvent: ItemEnqueued = {
     ...messageDownloadedEvent,
     id: '550e8400-e29b-41d4-a716-446655440001',
-    source:
-      '/nhs/england/notify/production/primary/data-plane/digitalletters/queue',
+    source: '/nhs/england/notify/production/primary/digitalletters/queue',
     type: 'uk.nhs.notify.digital.letters.queue.item.enqueued.v1',
     time: '2023-06-20T12:00:00.250Z',
     recordedtime: '2023-06-20T12:00:00.250Z',
diff --git a/lambdas/ttl-create-lambda/src/__tests__/data.ts b/lambdas/ttl-create-lambda/src/__tests__/data.ts
index b0c36fa18..5ebc7c47f 100644
--- a/lambdas/ttl-create-lambda/src/__tests__/data.ts
+++ b/lambdas/ttl-create-lambda/src/__tests__/data.ts
@@ -3,10 +3,10 @@ import { MESHInboxMessageDownloaded } from 'digital-letters-events';
 export const messageDownloadedEvent: MESHInboxMessageDownloaded = {
   id: '550e8400-e29b-41d4-a716-446655440001',
   specversion: '1.0',
-  source:
-    '/nhs/england/notify/production/primary/data-plane/digitalletters/mesh',
+  source: '/nhs/england/notify/production/primary/digitalletters/mesh',
   subject:
     'customer/920fca11-596a-4eca-9c47-99f624614658/recipient/769acdd4-6a47-496f-999f-76a6fd2c3959',
+  plane: 'data',
   type: 'uk.nhs.notify.digital.letters.mesh.inbox.message.downloaded.v1',
   time: '2023-06-20T12:00:00Z',
   recordedtime: '2023-06-20T12:00:00.250Z',
diff --git a/lambdas/ttl-handle-expiry-lambda/src/__tests__/apis/dynamodb-stream-handler.test.ts b/lambdas/ttl-handle-expiry-lambda/src/__tests__/apis/dynamodb-stream-handler.test.ts
index ef3bee90b..b0b033f4a 100644
--- a/lambdas/ttl-handle-expiry-lambda/src/__tests__/apis/dynamodb-stream-handler.test.ts
+++ b/lambdas/ttl-handle-expiry-lambda/src/__tests__/apis/dynamodb-stream-handler.test.ts
@@ -33,11 +33,12 @@ const mockEvent: DynamoDBStreamEvent = {
               id: { S: '550e8400-e29b-41d4-a716-446655440001' },
               specversion: { S: '1.0' },
               source: {
-                S: '/nhs/england/notify/production/primary/data-plane/digitalletters/mesh',
+                S: '/nhs/england/notify/production/primary/digitalletters/mesh',
               },
               subject: {
                 S: 'customer/920fca11-596a-4eca-9c47-99f624614658/recipient/769acdd4-6a47-496f-999f-76a6fd2c3959',
               },
+              plane: { S: 'data' },
               type: {
                 S: 'uk.nhs.notify.digital.letters.mesh.inbox.message.downloaded.v1',
               },
@@ -108,8 +109,7 @@ describe('createHandler', () => {
       [
         expect.objectContaining({
           specversion: '1.0',
-          source:
-            '/nhs/england/notify/production/primary/data-plane/digitalletters/queue',
+          source: '/nhs/england/notify/production/primary/digitalletters/queue',
           subject:
             'customer/920fca11-596a-4eca-9c47-99f624614658/recipient/769acdd4-6a47-496f-999f-76a6fd2c3959',
           type: 'uk.nhs.notify.digital.letters.queue.item.dequeued.v1',
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-event-bus-profile.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-event-bus-profile.schema.yaml
index 94d77a7f7..c59f54cb0 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-event-bus-profile.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-event-bus-profile.schema.yaml
@@ -14,6 +14,6 @@ properties:
         pattern: ^uk\.nhs\.notify\.digital\.letters\.eventbus\.[a-z0-9]+(?:\.[a-z0-9]+)*\.v[0-9]+$
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/(data-plane|control-plane)/digitalletters/eventbus
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/eventbus
     minLength: 40
     format: uri-reference
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-fhir-profile.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-fhir-profile.schema.yaml
index dc0000d3e..ccb4cd715 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-fhir-profile.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-fhir-profile.schema.yaml
@@ -14,6 +14,6 @@ properties:
         pattern: ^uk\.nhs\.notify\.digital\.letters\.fhir\.[a-z0-9]+(?:\.[a-z0-9]+)*\.v[0-9]+$
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/(data-plane|control-plane)/digitalletters/fhir
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/fhir
     minLength: 40
     format: uri-reference
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-letter-profile.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-letter-profile.schema.yaml
index 8b6471279..b23440751 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-letter-profile.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-letter-profile.schema.yaml
@@ -14,6 +14,6 @@ properties:
         pattern: ^uk\.nhs\.notify\.digital\.letters\.letter\.[a-z0-9]+(?:\.[a-z0-9]+)*\.v[0-9]+$
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/(data-plane|control-plane)/digitalletters/letter
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/letter
     minLength: 40
     format: uri-reference
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-mesh-profile.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-mesh-profile.schema.yaml
index e778f4aba..18e33d731 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-mesh-profile.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-mesh-profile.schema.yaml
@@ -14,6 +14,6 @@ properties:
         pattern: ^uk\.nhs\.notify\.digital\.letters\.mesh\.[a-z0-9]+(?:\.[a-z0-9]+)*\.v[0-9]+$
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/(data-plane|control-plane)/digitalletters/mesh
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/mesh
     minLength: 40
     format: uri-reference
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-messages-profile.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-messages-profile.schema.yaml
index 694f3b694..03751d157 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-messages-profile.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-messages-profile.schema.yaml
@@ -14,6 +14,6 @@ properties:
         pattern: ^uk\.nhs\.notify\.digital\.letters\.messages\.[a-z0-9]+(?:\.[a-z0-9]+)*\.v[0-9]+$
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/(data-plane|control-plane)/digitalletters/messages
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/messages
     minLength: 40
     format: uri-reference
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-pdm-profile.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-pdm-profile.schema.yaml
index e3ad7e1a5..09405d0c3 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-pdm-profile.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-pdm-profile.schema.yaml
@@ -14,6 +14,6 @@ properties:
         pattern: ^uk\.nhs\.notify\.digital\.letters\.pdm\.[a-z0-9]+(?:\.[a-z0-9]+)*\.v[0-9]+$
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/(data-plane|control-plane)/digitalletters/pdm
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/pdm
     minLength: 40
     format: uri-reference
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-print-profile.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-print-profile.schema.yaml
index 2023a9bc0..972775549 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-print-profile.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-print-profile.schema.yaml
@@ -14,6 +14,6 @@ properties:
         pattern: ^uk\.nhs\.notify\.digital\.letters\.print\.[a-z0-9]+(?:\.[a-z0-9]+)*\.v[0-9]+$
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/(data-plane|control-plane)/digitalletters/print
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/print
     minLength: 40
     format: uri-reference
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-profile.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-profile.schema.yaml
index b4a26e68c..a2aaab67d 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-profile.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-profile.schema.yaml
@@ -14,6 +14,10 @@ properties:
         pattern: ^uk\.nhs\.notify\.digital\.letters\.[a-z0-9]+(?:\.[a-z0-9]+)*\.v[0-9]+$
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/(data-plane|control-plane)/digitalletters
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters
     minLength: 40
     format: uri-reference
+  plane:
+    type: string
+    description: "The plane on which the event is emitted."
+    const: "data"
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-queue-profile.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-queue-profile.schema.yaml
index 430c44d2e..e5c9c94ad 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-queue-profile.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-queue-profile.schema.yaml
@@ -14,6 +14,6 @@ properties:
         pattern: ^uk\.nhs\.notify\.digital\.letters\.queue\.[a-z0-9]+(?:\.[a-z0-9]+)*\.v[0-9]+$
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/(data-plane|control-plane)/digitalletters/queue
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/queue
     minLength: 40
     format: uri-reference
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-reporting-profile.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-reporting-profile.schema.yaml
index d3dc20767..53d6995d0 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-reporting-profile.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-reporting-profile.schema.yaml
@@ -14,6 +14,6 @@ properties:
         pattern: ^uk\.nhs\.notify\.digital\.letters\.reporting\.[a-z0-9]+(?:\.[a-z0-9]+)*\.v[0-9]+$
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/(data-plane|control-plane)/digitalletters/reporting
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/reporting
     minLength: 40
     format: uri-reference
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-viewer-profile.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-viewer-profile.schema.yaml
index d77365de1..5b38a0b9b 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-viewer-profile.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/digital-letters-viewer-profile.schema.yaml
@@ -14,6 +14,6 @@ properties:
         pattern: ^uk\.nhs\.notify\.digital\.letters\.viewer\.[a-z0-9]+(?:\.[a-z0-9]+)*\.v[0-9]+$
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/(data-plane|control-plane)/digitalletters/viewer
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/viewer
     minLength: 40
     format: uri-reference
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.letter.available.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.letter.available.v1.schema.yaml
index 9e22ed8f6..aab869498 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.letter.available.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.letter.available.v1.schema.yaml
@@ -10,7 +10,7 @@ properties:
     description: Concrete versioned event type string for this example event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/letter
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/letter
     description: Event source for digital letters  examples.
 
   dataschema:
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.mesh.inbox.message.acknowledged.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.mesh.inbox.message.acknowledged.v1.schema.yaml
index d008704a9..b254640c1 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.mesh.inbox.message.acknowledged.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.mesh.inbox.message.acknowledged.v1.schema.yaml
@@ -10,7 +10,7 @@ properties:
     description: Concrete versioned event type string for this event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/mesh
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/mesh
     description: Event source for digital letters.
 
   dataschema:
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.mesh.inbox.message.downloaded.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.mesh.inbox.message.downloaded.v1.schema.yaml
index ffb6d8168..bee428575 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.mesh.inbox.message.downloaded.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.mesh.inbox.message.downloaded.v1.schema.yaml
@@ -10,7 +10,7 @@ properties:
     description: Concrete versioned event type string for this event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/mesh
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/mesh
     description: Event source for digital letters.
 
   dataschema:
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.mesh.inbox.message.invalid.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.mesh.inbox.message.invalid.v1.schema.yaml
index 70e9907c0..8fc828ec1 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.mesh.inbox.message.invalid.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.mesh.inbox.message.invalid.v1.schema.yaml
@@ -10,7 +10,7 @@ properties:
     description: Concrete versioned event type string for this event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/mesh
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/mesh
     description: Event source for digital letters.
 
   dataschema:
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.mesh.inbox.message.received.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.mesh.inbox.message.received.v1.schema.yaml
index b41128d40..c48d298c6 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.mesh.inbox.message.received.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.mesh.inbox.message.received.v1.schema.yaml
@@ -10,7 +10,7 @@ properties:
     description: Concrete versioned event type string for this event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/mesh
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/mesh
     description: Event source for digital letters.
 
   dataschema:
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.messages.request.rejected.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.messages.request.rejected.v1.schema.yaml
index d1984c0af..ae9570c21 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.messages.request.rejected.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.messages.request.rejected.v1.schema.yaml
@@ -10,7 +10,7 @@ properties:
     description: Concrete versioned event type string for this event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/messages
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/messages
     description: Event source for digital letters.
 
   dataschema:
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.messages.request.skipped.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.messages.request.skipped.v1.schema.yaml
index fb86ac3c9..dd5d958af 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.messages.request.skipped.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.messages.request.skipped.v1.schema.yaml
@@ -10,7 +10,7 @@ properties:
     description: Concrete versioned event type string for this event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/messages
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/messages
     description: Event source for digital letters.
 
   dataschema:
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.messages.request.submitted.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.messages.request.submitted.v1.schema.yaml
index 8b2167105..68edf4510 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.messages.request.submitted.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.messages.request.submitted.v1.schema.yaml
@@ -10,7 +10,7 @@ properties:
     description: Concrete versioned event type string for this event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/messages
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/messages
     description: Event source for digital letters.
 
   dataschema:
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.pdm.resource.available.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.pdm.resource.available.v1.schema.yaml
index 9ff20626d..15253dd4e 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.pdm.resource.available.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.pdm.resource.available.v1.schema.yaml
@@ -10,7 +10,7 @@ properties:
     description: Concrete versioned event type string for this event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/pdm
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/pdm
     description: Event source for digital letters.
 
   dataschema:
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.pdm.resource.retries.exceeded.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.pdm.resource.retries.exceeded.v1.schema.yaml
index ccbeb08b4..46b9f2402 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.pdm.resource.retries.exceeded.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.pdm.resource.retries.exceeded.v1.schema.yaml
@@ -10,7 +10,7 @@ properties:
     description: Concrete versioned event type string for this event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/pdm
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/pdm
     description: Event source for digital letters.
 
   dataschema:
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.pdm.resource.submission.rejected.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.pdm.resource.submission.rejected.v1.schema.yaml
index 8d8410d90..8e749904b 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.pdm.resource.submission.rejected.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.pdm.resource.submission.rejected.v1.schema.yaml
@@ -11,7 +11,7 @@ properties:
     description: Concrete versioned event type string for this event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/pdm
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/pdm
     description: Event source for digital letters.
 
   dataschema:
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.pdm.resource.submitted.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.pdm.resource.submitted.v1.schema.yaml
index 8f882c2bb..4e6c647e3 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.pdm.resource.submitted.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.pdm.resource.submitted.v1.schema.yaml
@@ -11,7 +11,7 @@ properties:
     description: Concrete versioned event type string for this event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/pdm
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/pdm
     description: Event source for digital letters.
 
   dataschema:
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.pdm.resource.unavailable.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.pdm.resource.unavailable.v1.schema.yaml
index 6417bba0d..7d10ab842 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.pdm.resource.unavailable.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.pdm.resource.unavailable.v1.schema.yaml
@@ -10,7 +10,7 @@ properties:
     description: Concrete versioned event type string for this event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/pdm
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/pdm
     description: Event source for digital letters.
 
   dataschema:
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.print.file.quarantined.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.print.file.quarantined.v1.schema.yaml
index 1d9e8b492..637cb8b67 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.print.file.quarantined.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.print.file.quarantined.v1.schema.yaml
@@ -10,7 +10,7 @@ properties:
     description: Concrete versioned event type string for this event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/print
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/print
     description: Event source for digital letters.
   dataschema:
     type: string
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.print.file.safe.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.print.file.safe.v1.schema.yaml
index 86811464d..e7851e4b1 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.print.file.safe.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.print.file.safe.v1.schema.yaml
@@ -10,7 +10,7 @@ properties:
     description: Concrete versioned event type string for this event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/print
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/print
     description: Event source for digital letters.
   dataschema:
     type: string
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.print.letter.transitioned.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.print.letter.transitioned.v1.schema.yaml
index 73780c95f..a455bc1c8 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.print.letter.transitioned.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.print.letter.transitioned.v1.schema.yaml
@@ -11,7 +11,7 @@ properties:
     description: Concrete versioned event type string for this event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/print
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/print
     description: Event source for digital letters.
 
   dataschema:
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.print.pdf.analysed.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.print.pdf.analysed.v1.schema.yaml
index 54f1829ff..5e95700f4 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.print.pdf.analysed.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.print.pdf.analysed.v1.schema.yaml
@@ -10,7 +10,7 @@ properties:
     description: Concrete versioned event type string for this event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/print
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/print
     description: Event source for digital letters.
   dataschema:
     type: string
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.queue.digital.letter.read.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.queue.digital.letter.read.v1.schema.yaml
index 533823937..d0555e9c2 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.queue.digital.letter.read.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.queue.digital.letter.read.v1.schema.yaml
@@ -10,7 +10,7 @@ properties:
     description: Concrete versioned event type string for this event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/queue
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/queue
     description: Event source for digital letters.
 
   dataschema:
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.queue.item.dequeued.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.queue.item.dequeued.v1.schema.yaml
index fcf71cff8..53b2fd811 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.queue.item.dequeued.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.queue.item.dequeued.v1.schema.yaml
@@ -10,7 +10,7 @@ properties:
     description: Concrete versioned event type string for this event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/queue
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/queue
     description: Event source for digital letters.
 
   dataschema:
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.queue.item.enqueued.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.queue.item.enqueued.v1.schema.yaml
index 9ced7d09a..4d37b17c6 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.queue.item.enqueued.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.queue.item.enqueued.v1.schema.yaml
@@ -10,7 +10,7 @@ properties:
     description: Concrete versioned event type string for this event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/queue
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/queue
     description: Event source for digital letters.
 
   dataschema:
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.reporting.generate.report.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.reporting.generate.report.v1.schema.yaml
index 60781d491..478d34f98 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.reporting.generate.report.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.reporting.generate.report.v1.schema.yaml
@@ -10,7 +10,7 @@ properties:
     description: Concrete versioned event type string for this event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/reporting
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/reporting
     description: Event source for digital letters.
 
   dataschema:
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.reporting.report.generated.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.reporting.report.generated.v1.schema.yaml
index 92ee9a949..33972180b 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.reporting.report.generated.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.reporting.report.generated.v1.schema.yaml
@@ -10,7 +10,7 @@ properties:
     description: Concrete versioned event type string for this event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/reporting
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/reporting
     description: Event source for digital letters.
 
   dataschema:
diff --git a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.reporting.report.sent.v1.schema.yaml b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.reporting.report.sent.v1.schema.yaml
index eeef261ad..0c0175599 100644
--- a/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.reporting.report.sent.v1.schema.yaml
+++ b/src/cloudevents/domains/digital-letters/2025-10-draft/events/uk.nhs.notify.digital.letters.reporting.report.sent.v1.schema.yaml
@@ -10,7 +10,7 @@ properties:
     description: Concrete versioned event type string for this event (.vN suffix).
   source:
     type: string
-    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/data-plane/digitalletters/reporting
+    pattern: ^/nhs/england/notify/(production|staging|development|uat)/(primary|secondary|dev-[0-9]+)/digitalletters/reporting
     description: Event source for digital letters.
 
   dataschema:
diff --git a/src/digital-letters-events/README.md b/src/digital-letters-events/README.md
index 4bec683b4..0017a0cb1 100644
--- a/src/digital-letters-events/README.md
+++ b/src/digital-letters-events/README.md
@@ -29,8 +29,9 @@ import { PDMResourceSubmitted } from 'digital-letters-events';
 
 const pdmResourceSubmittedEvent: PDMResourceSubmitted = {
     type: 'uk.nhs.notify.digital.letters.pdm.resource.submitted.v1',
+    plane : 'data',
     source:
-      '/nhs/england/notify/staging/dev-647563337/data-plane/digitalletters/pdm',
+      '/nhs/england/notify/staging/dev-647563337/digitalletters/pdm',
     dataschema:
       'https://notify.nhs.uk/cloudevents/schemas/digital-letters/2025-10-draft/data/digital-letters-pdm-resource-submitted-data.schema.json',
     specversion: '1.0',
@@ -96,7 +97,8 @@ try:
     # Validate and parse an event
     event_data = {
         "type": "uk.nhs.notify.digital.letters.pdm.resource.submitted.v1",
-        "source": "/nhs/england/notify/staging/dev-647563337/data-plane/digitalletters/pdm",
+        "plane": "data",
+        "source": "/nhs/england/notify/staging/dev-647563337/digitalletters/pdm",
         "dataschema": "https://notify.nhs.uk/cloudevents/schemas/digital-letters/2025-10-draft/data/digital-letters-pdm-resource-submitted-data.schema.json",
         "specversion": "1.0",
         "id": "0249e529-f947-4012-819e-b634eb71be79",
diff --git a/src/typescript-schema-generator/PLAN.md b/src/typescript-schema-generator/PLAN.md
index 69af34637..385638ce1 100644
--- a/src/typescript-schema-generator/PLAN.md
+++ b/src/typescript-schema-generator/PLAN.md
@@ -491,7 +491,7 @@ describe('LetterAvailable', () => {
   it('should create instance with valid data', () => {
     const event = new LetterAvailableBuilder()
       .withType('uk.nhs.notify.digital.letters.letter.available.v1')
-      .withSource('/nhs/england/notify/development/primary/data-plane/digitalletters/letter')
+      .withSource('/nhs/england/notify/development/primary/digitalletters/letter')
       .withData(/* ... */)
       .build();
 
@@ -551,7 +551,7 @@ const client = new CloudEventClient({
 
 const event = new LetterAvailable({
   type: 'uk.nhs.notify.digital.letters.letter.available.v1',
-  source: '/nhs/england/notify/development/primary/data-plane/digitalletters/letter',
+  source: '/nhs/england/notify/development/primary/digitalletters/letter',
   data: { /* ... */ }
 });
 
diff --git a/tests/playwright/digital-letters-component-tests/core-notify.component.spec.ts b/tests/playwright/digital-letters-component-tests/core-notify.component.spec.ts
index de9e137fd..9b94f70a9 100644
--- a/tests/playwright/digital-letters-component-tests/core-notify.component.spec.ts
+++ b/tests/playwright/digital-letters-component-tests/core-notify.component.spec.ts
@@ -21,8 +21,8 @@ import { v4 as uuidv4 } from 'uuid';
 
 const baseEvent: Omit<PDMResourceAvailable, 'id' | 'data'> = {
   specversion: '1.0',
-  source:
-    '/nhs/england/notify/production/primary/data-plane/digitalletters/pdm',
+  plane: 'data',
+  source: '/nhs/england/notify/production/primary/digitalletters/pdm',
   subject:
     'customer/920fca11-596a-4eca-9c47-99f624614658/recipient/769acdd4-6a47-496f-999f-76a6fd2c3959',
   type: 'uk.nhs.notify.digital.letters.pdm.resource.available.v1',
diff --git a/tests/playwright/digital-letters-component-tests/file-scanner.component.spec.ts b/tests/playwright/digital-letters-component-tests/file-scanner.component.spec.ts
index a1c7e5836..aa904277f 100644
--- a/tests/playwright/digital-letters-component-tests/file-scanner.component.spec.ts
+++ b/tests/playwright/digital-letters-component-tests/file-scanner.component.spec.ts
@@ -58,8 +58,9 @@ test('should extract PDF from DocumentReference and store in unscanned bucket wi
     [
       {
         id: eventId,
+        plane: 'data',
         specversion: '1.0',
-        source: `/nhs/england/notify/development/dev-1/data-plane/digitalletters/queue`,
+        source: `/nhs/england/notify/development/dev-1/digitalletters/queue`,
         subject: `message/${messageReference}`,
         type: 'uk.nhs.notify.digital.letters.queue.item.dequeued.v1',
         time: eventTime,
@@ -125,7 +126,8 @@ test('should handle validation errors by sending messages to DLQ', async () => {
       {
         id: eventId,
         specversion: '1.0',
-        source: `/nhs/england/notify/development/dev-1/data-plane/digitalletters/queue`,
+        plane: 'data',
+        source: `/nhs/england/notify/development/dev-1/digitalletters/queue`,
         subject: `message/${messageReference}`,
         type: 'uk.nhs.notify.digital.letters.queue.item.dequeued.v1',
         time: eventTime,
diff --git a/tests/playwright/digital-letters-component-tests/mesh-acknowledge.component.spec.ts b/tests/playwright/digital-letters-component-tests/mesh-acknowledge.component.spec.ts
index a55e148bb..10b11b3e2 100644
--- a/tests/playwright/digital-letters-component-tests/mesh-acknowledge.component.spec.ts
+++ b/tests/playwright/digital-letters-component-tests/mesh-acknowledge.component.spec.ts
@@ -24,8 +24,8 @@ test.describe('Digital Letters - Mesh Acknowledger', () => {
   const validMessageDownloadedEvent: MESHInboxMessageDownloaded = {
     id: uuidv4(),
     specversion: '1.0',
-    source:
-      '/nhs/england/notify/production/primary/data-plane/digitalletters/mesh',
+    plane: 'data',
+    source: '/nhs/england/notify/production/primary/digitalletters/mesh',
     subject:
       'customer/920fca11-596a-4eca-9c47-99f624614658/recipient/769acdd4-6a47-496f-999f-76a6fd2c3959',
     type: 'uk.nhs.notify.digital.letters.mesh.inbox.message.downloaded.v1',
diff --git a/tests/playwright/digital-letters-component-tests/mesh-poll-download.component.spec.ts b/tests/playwright/digital-letters-component-tests/mesh-poll-download.component.spec.ts
index 7fde42e51..e57408762 100644
--- a/tests/playwright/digital-letters-component-tests/mesh-poll-download.component.spec.ts
+++ b/tests/playwright/digital-letters-component-tests/mesh-poll-download.component.spec.ts
@@ -122,8 +122,8 @@ test.describe('Digital Letters - MESH Poll and Download', () => {
         {
           id: uuidv4(),
           specversion: '1.0',
-          source:
-            '/nhs/england/notify/development/primary/data-plane/digitalletters/mesh',
+          plane: 'data',
+          source: '/nhs/england/notify/development/primary/digitalletters/mesh',
           subject:
             'customer/00000000-0000-0000-0000-000000000000/recipient/00000000-0000-0000-0000-000000000000',
           type: 'uk.nhs.notify.digital.letters.mesh.inbox.message.received.v1',
diff --git a/tests/playwright/digital-letters-component-tests/pdm-poll.component.spec.ts b/tests/playwright/digital-letters-component-tests/pdm-poll.component.spec.ts
index 8d31cfb8d..d55cd9f66 100644
--- a/tests/playwright/digital-letters-component-tests/pdm-poll.component.spec.ts
+++ b/tests/playwright/digital-letters-component-tests/pdm-poll.component.spec.ts
@@ -16,8 +16,8 @@ import { v4 as uuidv4 } from 'uuid';
 
 const baseEvent = {
   specversion: '1.0',
-  source:
-    '/nhs/england/notify/production/primary/data-plane/digitalletters/pdm',
+  plane: 'data',
+  source: '/nhs/england/notify/production/primary/digitalletters/pdm',
   subject:
     'customer/920fca11-596a-4eca-9c47-99f624614658/recipient/769acdd4-6a47-496f-999f-76a6fd2c3959',
   time: '2023-06-20T12:00:00Z',
diff --git a/tests/playwright/digital-letters-component-tests/pdm-uploader.component.spec.ts b/tests/playwright/digital-letters-component-tests/pdm-uploader.component.spec.ts
index 5b2993eb2..4d42a172b 100644
--- a/tests/playwright/digital-letters-component-tests/pdm-uploader.component.spec.ts
+++ b/tests/playwright/digital-letters-component-tests/pdm-uploader.component.spec.ts
@@ -36,8 +36,8 @@ const pdmRequest = {
 
 const baseEvent = {
   specversion: '1.0',
-  source:
-    '/nhs/england/notify/production/primary/data-plane/digitalletters/mesh',
+  plane: 'data',
+  source: '/nhs/england/notify/production/primary/digitalletters/mesh',
   subject:
     'customer/920fca11-596a-4eca-9c47-99f624614658/recipient/769acdd4-6a47-496f-999f-76a6fd2c3959',
   type: 'uk.nhs.notify.digital.letters.mesh.inbox.message.downloaded.v1',
diff --git a/tests/playwright/digital-letters-component-tests/print-analyser.component.spec.ts b/tests/playwright/digital-letters-component-tests/print-analyser.component.spec.ts
index 46720477c..a83db30a0 100644
--- a/tests/playwright/digital-letters-component-tests/print-analyser.component.spec.ts
+++ b/tests/playwright/digital-letters-component-tests/print-analyser.component.spec.ts
@@ -17,8 +17,8 @@ import { putFileS3 } from 'utils';
 export const fileSafeEvent: FileSafe = {
   id: '550e8400-e29b-41d4-a716-446655440001',
   specversion: '1.0',
-  source:
-    '/nhs/england/notify/production/primary/data-plane/digitalletters/print',
+  plane: 'data',
+  source: '/nhs/england/notify/production/primary/digitalletters/print',
   subject:
     'letter-origin/digital-letters/letter/f47ac10b-58cc-4372-a567-0e02b2c3d479',
   type: 'uk.nhs.notify.digital.letters.print.file.safe.v1',
diff --git a/tests/playwright/digital-letters-component-tests/print-sender.component.spec.ts b/tests/playwright/digital-letters-component-tests/print-sender.component.spec.ts
index b761c54ab..ea66b38f2 100644
--- a/tests/playwright/digital-letters-component-tests/print-sender.component.spec.ts
+++ b/tests/playwright/digital-letters-component-tests/print-sender.component.spec.ts
@@ -27,8 +27,8 @@ test.describe('Digital Letters - Print Sender', () => {
         {
           id: letterId,
           specversion: '1.0',
-          source:
-            '/nhs/england/notify/production/primary/data-plane/digitalletters/print',
+          plane: 'data',
+          source: '/nhs/england/notify/production/primary/digitalletters/print',
           subject:
             'customer/920fca11-596a-4eca-9c47-99f624614658/recipient/769acdd4-6a47-496f-999f-76a6fd2c3959',
           type: 'uk.nhs.notify.digital.letters.print.pdf.analysed.v1',
@@ -76,8 +76,8 @@ test.describe('Digital Letters - Print Sender', () => {
     const event = {
       id: uuidv4(),
       specversion: '1.0',
-      source:
-        '/nhs/england/notify/production/primary/data-plane/digitalletters/print',
+      plane: 'data',
+      source: '/nhs/england/notify/production/primary/digitalletters/print',
       subject:
         'customer/920fca11-596a-4eca-9c47-99f624614658/recipient/769acdd4-6a47-496f-999f-76a6fd2c3959',
       type: 'uk.nhs.notify.digital.letters.print.pdf.analysed.v1',
diff --git a/tests/playwright/digital-letters-component-tests/send-reports-trust.component.spec.ts b/tests/playwright/digital-letters-component-tests/send-reports-trust.component.spec.ts
index 2a8311680..96ee04f3f 100644
--- a/tests/playwright/digital-letters-component-tests/send-reports-trust.component.spec.ts
+++ b/tests/playwright/digital-letters-component-tests/send-reports-trust.component.spec.ts
@@ -25,8 +25,9 @@ test.describe('Digital Letters - Send reports to Trust', () => {
         {
           id: uuidv4(),
           specversion: '1.0',
+          plane: 'data',
           source:
-            '/nhs/england/notify/development/dev-12345/data-plane/digitalletters/reporting',
+            '/nhs/england/notify/development/dev-12345/digitalletters/reporting',
           subject: `report/${uuidv4()}`,
           type: 'uk.nhs.notify.digital.letters.reporting.report.generated.v1',
           time: new Date().toISOString(),
diff --git a/tests/playwright/digital-letters-component-tests/ttl-create.component.spec.ts b/tests/playwright/digital-letters-component-tests/ttl-create.component.spec.ts
index 6a5d35fa2..c595d9e69 100644
--- a/tests/playwright/digital-letters-component-tests/ttl-create.component.spec.ts
+++ b/tests/playwright/digital-letters-component-tests/ttl-create.component.spec.ts
@@ -27,8 +27,8 @@ test.describe('Digital Letters - Create TTL', () => {
   const baseEvent: MESHInboxMessageDownloaded = {
     id: 'id',
     specversion: '1.0',
-    source:
-      '/nhs/england/notify/production/primary/data-plane/digitalletters/mesh',
+    plane: 'data',
+    source: '/nhs/england/notify/production/primary/digitalletters/mesh',
     subject:
       'customer/920fca11-596a-4eca-9c47-99f624614658/recipient/769acdd4-6a47-496f-999f-76a6fd2c3959',
     type: 'uk.nhs.notify.digital.letters.mesh.inbox.message.downloaded.v1',
diff --git a/tests/playwright/digital-letters-component-tests/ttl-handle.component.spec.ts b/tests/playwright/digital-letters-component-tests/ttl-handle.component.spec.ts
index b726abe00..b01ce3381 100644
--- a/tests/playwright/digital-letters-component-tests/ttl-handle.component.spec.ts
+++ b/tests/playwright/digital-letters-component-tests/ttl-handle.component.spec.ts
@@ -15,8 +15,8 @@ test.describe('Digital Letters - Handle TTL', () => {
   const baseEvent: MESHInboxMessageDownloaded = {
     id: 'sample-id',
     specversion: '1.0',
-    source:
-      '/nhs/england/notify/production/primary/data-plane/digitalletters/mesh',
+    plane: 'data',
+    source: '/nhs/england/notify/production/primary/digitalletters/mesh',
     subject:
       'customer/920fca11-596a-4eca-9c47-99f624614658/recipient/769acdd4-6a47-496f-999f-76a6fd2c3959',
     type: 'uk.nhs.notify.digital.letters.mesh.inbox.message.downloaded.v1',
diff --git a/tests/playwright/helpers/event-builders.ts b/tests/playwright/helpers/event-builders.ts
index 6383a37fe..ee6d09723 100644
--- a/tests/playwright/helpers/event-builders.ts
+++ b/tests/playwright/helpers/event-builders.ts
@@ -11,7 +11,8 @@ import {
 function buildBaseEvent(sourceComponent: string, time: string) {
   return {
     specversion: '1.0',
-    source: `/nhs/england/notify/production/primary/data-plane/digitalletters/${sourceComponent}`,
+    plane: 'data',
+    source: `/nhs/england/notify/production/primary/digitalletters/${sourceComponent}`,
     subject:
       'customer/920fca11-596a-4eca-9c47-99f624614658/recipient/769acdd4-6a47-496f-999f-76a6fd2c3959',
     time,
diff --git a/tests/playwright/helpers/report-helpers.ts b/tests/playwright/helpers/report-helpers.ts
index 6e02b8b29..a337654d6 100644
--- a/tests/playwright/helpers/report-helpers.ts
+++ b/tests/playwright/helpers/report-helpers.ts
@@ -257,8 +257,9 @@ export async function publishGenerateReport(
       {
         id: generateReportEventId,
         specversion: '1.0',
+        plane: 'data',
         source:
-          '/nhs/england/notify/production/primary/data-plane/digitalletters/reporting',
+          '/nhs/england/notify/production/primary/digitalletters/reporting',
         subject:
           'customer/920fca11-596a-4eca-9c47-99f624614658/recipient/769acdd4-6a47-496f-999f-76a6fd2c3959',
         type: 'uk.nhs.notify.digital.letters.reporting.generate.report.v1',
@@ -291,8 +292,9 @@ export async function publishEventNotInReports(senderId: string) {
       {
         id: skippedEventId,
         specversion: '1.0',
+        plane: 'data',
         source:
-          '/nhs/england/notify/production/primary/data-plane/digitalletters/messages',
+          '/nhs/england/notify/production/primary/digitalletters/messages',
         subject:
           'customer/920fca11-596a-4eca-9c47-99f624614658/recipient/769acdd4-6a47-496f-999f-76a6fd2c3959',
         type: 'uk.nhs.notify.digital.letters.messages.request.skipped.v1',
diff --git a/utils/py-utils/dl_utils/__tests__/test_event_publisher.py b/utils/py-utils/dl_utils/__tests__/test_event_publisher.py
index 9cdd3bfca..9c922fb95 100644
--- a/utils/py-utils/dl_utils/__tests__/test_event_publisher.py
+++ b/utils/py-utils/dl_utils/__tests__/test_event_publisher.py
@@ -44,7 +44,8 @@ def valid_cloud_event():
         'profilepublished': '2025-10',
         'id': '550e8400-e29b-41d4-a716-446655440001',
         'specversion': '1.0',
-        'source': '/nhs/england/notify/production/primary/data-plane/digitalletters/mesh',
+        'plane': 'data',
+        'source': '/nhs/england/notify/production/primary/digitalletters/mesh',
         'subject': 'customer/920fca11-596a-4eca-9c47-99f624614658/recipient/769acdd4-6a47-496f-999f-76a6fd2c3959',
         'type': 'uk.nhs.notify.digital.letters.mesh.inbox.message.received.v1',
         'time': '2023-06-20T12:00:00Z',
@@ -69,7 +70,8 @@ def valid_cloud_event2():
         'profilepublished': '2025-10',
         'id': '550e8400-e29b-41d4-a716-446655440002',
         'specversion': '1.0',
-        'source': '/nhs/england/notify/development/primary/data-plane/digitalletters/mesh',
+        'plane': 'data',
+        'source': '/nhs/england/notify/development/primary/digitalletters/mesh',
         'subject': 'customer/920fca11-596a-4eca-9c47-99f624614658/recipient/769acdd4-6a47-496f-999f-76a6fd2c3959',
         'type': 'uk.nhs.notify.digital.letters.mesh.inbox.message.received.v1',
         'time': '2023-06-20T12:00:00Z',
diff --git a/utils/utils/src/__tests__/event-publisher/event-publisher.test.ts b/utils/utils/src/__tests__/event-publisher/event-publisher.test.ts
index 34b081e82..83bd09538 100644
--- a/utils/utils/src/__tests__/event-publisher/event-publisher.test.ts
+++ b/utils/utils/src/__tests__/event-publisher/event-publisher.test.ts
@@ -31,13 +31,13 @@ const testConfig: EventPublisherDependencies = {
 
 const event: TestEvent = {
   id: '550e8400-e29b-41d4-a716-446655440001',
-  source: '/nhs/england/notify/production/primary/data-plane/digital-letters',
+  source: '/nhs/england/notify/production/primary/digital-letters',
   type: 'uk.nhs.notify.digital.letters.sent.v1',
 };
 
 const event2: TestEvent = {
   id: '550e8400-e29b-41d4-a716-446655440002',
-  source: '/nhs/england/notify/development/primary/data-plane/digital-letters',
+  source: '/nhs/england/notify/development/primary/digital-letters',
   type: 'uk.nhs.notify.digital.letters.sent.v2',
 };