diff --git a/packages/app/CHANGELOG.md b/packages/app/CHANGELOG.md
index 56233669e2..5cb4b32c80 100644
--- a/packages/app/CHANGELOG.md
+++ b/packages/app/CHANGELOG.md
@@ -7,6 +7,8 @@ See [Conventional Commits](https://conventionalcommits.org) for commit guideline
 
 **Note:** Version bump only for package @react-native-firebase/app
 
+**Note:** You *may* need to re-download your firebase config files (android json / ios plist) to handle changes in the underlying SDKs as they migrate from instance id to installations. A symptom would be `NativeFirebaseError: [messaging/unknown] FIS_AUTH_ERROR`. [Upstream reference doc](https://github.com/firebase/firebase-android-sdk/blob/master/firebase-installations/REQUIRED_FIREBASE_OPTIONS_ANDROID.md#what-do-i-need-to-do) / [Related issue #4466](https://github.com/invertase/react-native-firebase/issues/4466)
+
 ## [8.4.5](https://github.com/invertase/react-native-firebase/compare/@react-native-firebase/app@8.4.4...@react-native-firebase/app@8.4.5) (2020-09-30)
 
 ### Bug Fixes