The smart dealers around here only have the units ordered previously by those on the reservation list - a long time ago. If someone decides not to buy their reserved unit then the dealer should go to his 'orphan' waiting list to find a buyer.
If you want one quickly, this is the way to go - especially if you have no preference to color, interior, add-ons, etc.
As to the 'test drive' vehicle, I suppose that it's sale would be up to the dealer.
Until the pipeline is completely filled and the reservations list down to 'zero' there won't be many of these sitting around on dealer lots for sale. . . far different from the US Automotive dealer business model that cranks out thousands of cars in hopes that someone is going to buy them all.