From reading this Forum, I don't believe there is a written law that says a dealer has to hold a customers vehicle for a certain amount of time. I do know the dealer is invoiced once the unit is shipped. I suspect they have a deadline to pay the invoice before penalties set in.
This game is like most others as no one wants to be liable for additional costs associated with the movement of goods.
Therefore I believe it's up to the dealership as to whether they want to hold a customers unit for an extended amount of time. I believe a good honest dealership would do everything within their power to help the customer as it multiplies their selling power as positive reviews and feedback as well as word of mouth dictates additional customers visiting their lot.
However, given today's economy and the ability for a crooked dealership to take advantage of an unsuspecting customer and sell the unit for well over MSRP, I suspect they will place the burden on the original customer to make good on the purchase as soon as possible once the unit hits the lot.
So! In a nut shell..... did you purchase from an honest dealer or a dishonest dealer?