diff --git a/ports/espressif/bootloader_components/main/bootloader_start.c b/ports/espressif/bootloader_components/main/bootloader_start.c
index c17921960..210f5ab48 100644
--- a/ports/espressif/bootloader_components/main/bootloader_start.c
+++ b/ports/espressif/bootloader_components/main/bootloader_start.c
@@ -236,6 +236,7 @@ static int selected_boot_partition(const bootloader_state_t *bs) {
             esp_rom_gpio_pad_pullup_only(PIN_BUTTON_UF2);
 
             // run the GPIO detection at least once even if UF2_DETECTION_DELAY_MS is set to zero
+            uint32_t const detection_delay_ms = UF2_DETECTION_DELAY_MS;
             uint32_t tm_start = esp_log_early_timestamp();
             do {
               if ( gpio_ll_get_level(&GPIO, PIN_BUTTON_UF2) == 0 ) {
@@ -243,7 +244,7 @@ static int selected_boot_partition(const bootloader_state_t *bs) {
                 boot_index = FACTORY_INDEX;
                 break;
               }
-            } while (UF2_DETECTION_DELAY_MS > (esp_log_early_timestamp() - tm_start) );
+            } while (detection_delay_ms > (esp_log_early_timestamp() - tm_start) );
 
             if (UF2_DETECTION_DELAY_MS > 0){
               board_led_off();