Forum member Falcon007 recently asked what his options were when a dealer sold the car he had already reserved with a deposit. Needless to say, he was very upset because the Golf R he wanted had a rare special-order color and it would take a long time to find another one.
The deposit was made by telephone and he had the VIN.
The manager contacted him to say that there was a re-organisation of employees at the dealer and the old manager took the sale with him and there was nothing he could do. You’ll need to read what Falcon007 decided to do by viewing the discussion here (reply #42).
The other replies are also interesting to read.