I would visit some ADs and strike up a conversation with them and see where that leads. You may get on the list, you may not. The "waiting list" often is not a real list, it is just a query of people interested in a specific piece. And depending on the AD, sometimes you get bumped when a bigger fish comes in and spends money. It is really all a game right now.
If you want the watch tomorrow, and you are willing to pay the premium, I would go for the grey market. We have a lot of great dealers here (and some in the UK) and you can buy with confidence when you check the
Buyers/Sellers Who's Who.
Whatever you pick, best of luck and welcome to the forums!