README.md in jets-0.9.0 vs README.md in jets-0.9.1

@@ -17,9 +17,11 @@
 * **AWS Lambda** is Functions as a Service. It allows you to upload and run functions without worrying about the underlying infrastructure.
 * **API Gateway** is the routing layer for Lambda. It is used to route REST URL endpoints to Lambda functions.
 
 The official documentation is at: [Ruby on Jets](http://rubyonjets.com).
 
+**Upgrading Note**: If you are upgrading Jets, please check on the [Upgrading Notes](http://rubyonjets.com/docs/upgrading/).
+
 Refer to the official docs for more info, but here's a quick intro.
 
 ### Jets Controllers
 
 A Jets controller handles a web request and renders a response.  Here's an example: