Update README.md - Added Announcements section (#475)

README.md

@@ -4,10 +4,12 @@
 
 Braintree Android Drop-In is a readymade UI that allows you to accept card and alternative payments in your Android app.
 
-:mega:  A new major version of the SDK is now available. See the [v6 migration guide](v6_MIGRATION_GUIDE.md) for details.
-
 <img alt="Screenshot of Drop-In" src="screenshots/vaulted-payment-methods.png" width="200"/>
 
+## 📣 Announcements
+- A new major version of the SDK is now available. See the [v6 migration guide](v6_MIGRATION_GUIDE.md) for details.
+- Upgrade your integration to continue accepting Braintree payments The SSL certificates for the Android SDK are set to expire by June 31, 2025. Upgrade to v6.16.0+ to continue using the Braintree SDK.
+
 ## Adding it to your project
 
 Add the dependency in your `build.gradle`: