GolfTi: I suppose it all depends on how much business any particular dealership has. If they haven't sold their allocated "one per month" in any given month then you may be able to get that allocated car at a reasonable discount without adversely affecting lead time. If on the other hand you have a dealership supplying one of these brokers that has an order in for 8 or 10 GTI/GTDs then there is going to be a wait.
I'd be interested to find out what will happen in my situation. I was the first to order a GTD at Pulman Sunderland. 2 days later I placed an order for another GTD on my dad's behalf and a lad I know from another forum placed a GTD order a day after that. When the salesman has been speaking to me, he has given me the impression that we'll all be getting ours late June/Early July, whereas I would expect us to be getting ours a month apart, with mine coming first. Will the "allocation" go out of the window if VW aren't currently as busy as they'd like to be and so have plenty of spare capacity for production?
Perhaps with a multi branch dealership like Pulman, if the Durham branch has sold none, maybe the Sunderland branch can grab Durham's allocation for that month etc.