Sadly I have just had to complain to our Account Manager about waiting so long to get a human response to a logged call.
It seems there has been a revamp, as below; this is the first I had heard about this.
Service Availability
And Performance Local Hours
P1 : 2 hour response, fix < 2 days
P2 : 4 hour response, fix < 3 days
P3 : Fix < 10 days