diff --git a/MIGRATION_GUIDE.md b/MIGRATION_GUIDE.md
index 2f6954f..7c33e07 100644
--- a/MIGRATION_GUIDE.md
+++ b/MIGRATION_GUIDE.md
@@ -1,5 +1,15 @@
 # Flutter v5.0.0 Migration Guide
 
+#### ⚠️ Migration Advisory for current OneSignal customers
+
+Our new [user-centric APIs and v5.x.x SDKs](https://onesignal.com/blog/unify-your-users-across-channels-and-devices/) offer an improved user and data management experience. However, they may not be at 1:1 feature parity with our previous versions yet.
+
+If you are migrating an existing app, we suggest using iOS and Android’s Phased Rollout capabilities to ensure that there are no unexpected issues or edge cases. Here is the documentation for each:
+
+- [iOS Phased Rollout](https://developer.apple.com/help/app-store-connect/update-your-app/release-a-version-update-in-phases/)
+- [Google Play Staged Rollouts](https://support.google.com/googleplay/android-developer/answer/6346149?hl=en)
+
+If you run into any challenges or have concerns, please contact our support team at support@onesignal.com
 
 # Intro
 
diff --git a/README.md b/README.md
index 8b12c29..28091d1 100644
--- a/README.md
+++ b/README.md
@@ -6,6 +6,19 @@
 
 ---
 
+#### ⚠️ Migration Advisory for current OneSignal customers
+
+Our new [user-centric APIs and v5.x.x SDKs](https://onesignal.com/blog/unify-your-users-across-channels-and-devices/) offer an improved user and data management experience. However, they may not be at 1:1 feature parity with our previous versions yet.
+
+If you are migrating an existing app, we suggest using iOS and Android’s Phased Rollout capabilities to ensure that there are no unexpected issues or edge cases. Here is the documentation for each:
+
+- [iOS Phased Rollout](https://developer.apple.com/help/app-store-connect/update-your-app/release-a-version-update-in-phases/)
+- [Google Play Staged Rollouts](https://support.google.com/googleplay/android-developer/answer/6346149?hl=en)
+
+If you run into any challenges or have concerns, please contact our support team at support@onesignal.com
+
+---
+
 [OneSignal](https://onesignal.com/) is a free email, sms, push notification, and in-app message service for mobile apps. This SDK makes it easy to integrate your Flutter iOS and/or Android apps with OneSignal.
 
 <p align="center"><img src="https://app.onesignal.com/images/android_and_ios_notification_image.gif" width="500" alt="Flutter Notification"></p>