EYZ. The rules state that transfer of control does not happen until a specific distance prior to GITEX, which is invariably after you want descent (especially from higher levels). It is up to the receiving controller if he descends you- but he is taking on risk unless he rings up every single time for confirmation of release (which gets REALLY tedious, and adds workload). Some controllers stick rigidly to the rules and won't descend until the release point, some stick to the rules and ring up every time for every a/c, and some controllers will bend the rules and give you descent if you prompt them with the info that BAH has no restriction. It's one of those things that management turn a blind eye to until something goes wrong- and then they hang you. It seems they delight in writing really restrictive rules, hope that guys will actually bend them for efficiency, but then hang you whenever it goes wrong. Doesn't happen at your airline?
I am a fan of giving blanket descent- to say, FL310 for every AUH arrival. It's about 50/50 for controllers in AUH ACC who accept/reject the blanket clearance (which is forbidden in the rules, regardless of how sensible or efficient it is). Give a few controllers from each centre an hour together to re-write rules, and it would be a great outcome. *Not going to happen.
John21UK. Drop into the centre. It is much easier to explain when you are looking at the radar. All the level restrictions in the area are for traffic management. And it all needs looking at- it just keeps getting busier!