If the CreateSubscriptionrequest was accepted but the deletion lock was not, the response message shall include the following HTTP/1.1 Warning header field:
Warning: 299 {+SERVICE}: Deletion Lock not granted.
If the request was rejected with an HTTP/1.1 403 status code because Filtered Global Subscription is not supported, the response message shall include the following HTTP/1.1 Warning header field:
Warning: 299 {+SERVICE}: The Origin-Server does not support Global Subscription Filtering.