Update group-permissions-for-apps.md

Author: jlichwa

articles/key-vault/general/group-permissions-for-apps.md

@@ -105,7 +105,7 @@ Id                    : 1cef38c4-388c-45a9-b5ae-3d88375e166a
 ```
 
 > [!WARNING]
-> Azure Ad Groups does not support Managed Identities. Only service and user principals are supported.
+> Azure AD Groups with Managed Identities require up to 8hr to refresh token and become effective.
 
 #### Users