add disclaimer for use cases

index.bs

@@ -403,7 +403,8 @@ Beyond that, the intended audiences for this document are the following main gro
 ## Use Cases ## {#sctn-use-cases}
 
 The below use case scenarios illustrate use of two very different types of [=authenticators=] and credentials across two common deployment types, 
-as well as outline further scenarios. Additional scenarios, including sample code, are given later in [[#sctn-sample-scenarios]].
+as well as outline further scenarios. Additional scenarios, including sample code, are given later in [[#sctn-sample-scenarios]]. 
+These examples are for illustrative purposes only, and feature availability may differ between client and authenticator implementations.
 
 ### Consumer with Multi-Device Credentials ### {#sctn-usecase-consumer-mdc}