diff --git a/libs/apexutil/TEST_MAPPING b/libs/apexutil/TEST_MAPPING
index f66a400..73848d3 100644
--- a/libs/apexutil/TEST_MAPPING
+++ b/libs/apexutil/TEST_MAPPING
@@ -1,3 +1,5 @@
+// When adding or removing tests here, don't forget to amend _all_modules list in
+// wireless/android/busytown/ath_config/configs/prod/avf/tests.gcl
 {
   "avf-presubmit" : [
     {