diff --git a/build.sh b/build.sh
index 8e5c30b45..48fae2c4d 100755
--- a/build.sh
+++ b/build.sh
@@ -2637,21 +2637,21 @@ requires_esp32_portable_app_slot() {
     && ! is_esp32_companion_build "$1"
 }
 
-is_esp32_c6_target() {
-  [[ "${PIO_ENV_BOARD_BY_NAME[$1]:-}" == esp32-c6-* ]]
-}
-
 requires_esp32_portable_size_ceiling() {
   local env_name=$1
 
   requires_esp32_portable_app_slot "$env_name" || return 1
 
-  # Arduino 3.x pulls substantially more WiFi runtime into ESP32-C6 images.
-  # These target-specific OTA siblings already used 1920 KiB or larger A/B app
-  # slots before the compact browser uploader was enabled, so retain their
-  # established partition contract and enforce the actual partition below.
-  if is_lora_ota_only_target "$env_name" && is_esp32_c6_target "$env_name"; then
-    return 1
+  # Arduino 3.x pulls substantially more WiFi runtime into ESP32-C6 and RC32
+  # images. These target-specific OTA siblings already use larger A/B slots:
+  # C6 boards declared at least 1920 KiB slots, while RC32 has always declared
+  # the two 0x640000 slots in default_16MB.csv. Retain those established
+  # partition contracts and enforce each image against its actual partition
+  # below instead of the unrelated legacy 1.25 MiB ceiling.
+  if is_lora_ota_only_target "$env_name"; then
+    case "${PIO_ENV_BOARD_BY_NAME[$env_name]:-}" in
+      esp32-c6-*|heltec-rc32) return 1 ;;
+    esac
   fi
 
   return 0
diff --git a/test/test_build_profiles.sh b/test/test_build_profiles.sh
index 8ca824d50..0d67faf1a 100644
--- a/test/test_build_profiles.sh
+++ b/test/test_build_profiles.sh
@@ -268,6 +268,21 @@ require(rak_usb, "build_flags", "FORCE_GPS_ALIVE")
 # aliases remain directly buildable, but canonical release resolution must
 # replace each with that exact board's Full target.
 init_project_context >/dev/null
+
+# Arduino-ESP32 3.x OTA-only targets that have always declared larger A/B
+# slots must be checked against their real partition table, not the legacy
+# 1.25 MiB portable ceiling. Keep that exception OTA-only so ordinary RC32
+# standard artifacts still retain the portable release contract.
+for rc32_ota_env in \
+    heltec_rc32_repeater_lora_ota_no_external_sensors \
+    heltec_rc32_without_display_repeater_lora_ota_no_external_sensors; do
+  if requires_esp32_portable_size_ceiling "$rc32_ota_env"; then
+    fail "$rc32_ota_env incorrectly inherited the legacy portable size ceiling"
+  fi
+done
+requires_esp32_portable_size_ceiling heltec_rc32_repeater \
+  || fail "ordinary RC32 repeater lost the portable size ceiling"
+
 while IFS='|' read -r source_env full_env build_base; do
   [ "${PIO_ENV_PLATFORM_BY_NAME[$full_env]:-}" = ESP32_PLATFORM ] \
     || fail "$full_env was not registered as ESP32 Full Companion"