diff --git a/nearby/README.md b/nearby/README.md
index 81d2199..8dac61c 100644
--- a/nearby/README.md
+++ b/nearby/README.md
@@ -55,6 +55,7 @@
 $ adb install /tmp/tethering.apex
 $ adb reboot
 
+NOTE: Developers should use AOSP by default, udc-mainline-prod should not be used unless for Google internal features.
 For udc-mainline-prod on Google internal host
 Build unbundled module using banchan
 $ source build/envsetup.sh