adding warning

Author: billmath

articles/active-directory/cloud-provisioning/concept-attributes.md

@@ -11,7 +11,7 @@ ms.devlang: na
 ms.topic: conceptual
 ms.tgt_pltfrm: na
 ms.workload: identity
-ms.date: 12/02/2019
+ms.date: 02/18/2019
 ms.subservice: hybrid
 ms.author: billmath
 
@@ -64,6 +64,9 @@ The following table lists common attributes and how they're synchronized to Azur
 |ProxyAdress|Direct|ProxyAddress|
 
 ## View the schema
+> [!WARNING]
+> You should not be using the service principal configuration to modify the attribute mappings.  This is not supported.
+
 To view the schema and verify it, follow these steps.
 
 1.  Go to [Graph Explorer](https://developer.microsoft.com/graph/graph-explorer).