Took this info of another forum for your info
I have just called the dealer and had a chat. They had all the information to hand and ran over everything with me.
We agreed on many points. The dealer KNEW already what customers were going to be concerned about. Was a very interesting conversation.
Bottom line is that next week they will be writing to customers on their list asking for a substantial sum of cash to secure their place on the waiting lists. Salesman said the final amount is down to his boss (then asked his boss) but likely to be £5,000 (inc deposit already placed).
I've left my deposit in place for the moment, but have no intention of handing over £4,500 next week at this point in time.