diff --git a/R/git.R b/R/git.R
index 6c8af65c..821e90a5 100644
--- a/R/git.R
+++ b/R/git.R
@@ -41,9 +41,8 @@ repo_check_branches <- function(client, repository) {
   branches_task <- Task$new(connect = client, task = branches_raw)
 
   task_res <- poll_task(branches_task, callback = NULL)
-  task_data <- task_res$get_data()
-  stopifnot(identical(task_data$type, "git-repo-ref-branch-array"))
-  branches <- purrr::map(task_data$data, ~ .x$branch)
+  branch_entries <- parse_repo_branches(task_res$get_data())
+  branches <- purrr::map(branch_entries, ~ .x$branch)
   purrr::set_names(branches, branches)
 }
 
@@ -56,13 +55,28 @@ repo_check_branches_ref <- function(client, repository) {
   branches_task <- Task$new(connect = client, task = branches_raw)
 
   task_res <- poll_task(branches_task, callback = NULL)
-  task_data <- task_res$get_data()
-  stopifnot(identical(task_data$type, "git-repo-ref-branch-array"))
-  branches <- purrr::map(task_data$data, ~ .x$branch)
-  refs <- purrr::map_chr(task_data$data, ~ .x$ref)
+  branch_entries <- parse_repo_branches(task_res$get_data())
+  branches <- purrr::map(branch_entries, ~ .x$branch)
+  refs <- purrr::map_chr(branch_entries, ~ .x$ref)
   purrr::set_names(refs, branches)
 }
 
+# Gracefully handle different formats of the /repo/branches task result
+parse_repo_branches <- function(task_data) {
+  if (identical(task_data$type, "git-repo-ref-branch-array")) {
+    task_data$data
+  } else if (identical(task_data$type, "git-repo-branches-result")) {
+    task_data$data$branches
+  } else {
+    stop(
+      glue::glue(
+        "Unexpected task result type '{task_data$type}' returned from the ",
+        "/repo/branches endpoint."
+      )
+    )
+  }
+}
+
 #' @rdname git
 #' @export
 repo_check_manifest_dirs <- function(client, repository, branch) {
diff --git a/tests/testthat/test-git.R b/tests/testthat/test-git.R
index d2f365eb..cff56256 100644
--- a/tests/testthat/test-git.R
+++ b/tests/testthat/test-git.R
@@ -72,3 +72,18 @@ with_mock_api({
     )
   })
 })
+
+test_that("parse_repo_branches handles both result shapes", {
+  entries <- list(
+    list(branch = "main", ref = strrep("a", 40)),
+    list(branch = "dev", ref = strrep("b", 40))
+  )
+  task_data_old <- list(type = "git-repo-ref-branch-array", data = entries)
+  expect_identical(parse_repo_branches(task_data_old), entries)
+
+  task_data_new <- list(
+    type = "git-repo-branches-result",
+    data = list(branches = entries, default_branch = "main")
+  )
+  expect_identical(parse_repo_branches(task_data_new), entries)
+})