i ordered a nissan juke in dec on wpms the ap was 900ish, in feb it went down to 631, all i had to do was speak to the dealer and they changed it. its a 10 minute thing.
if you are set on a particuular car and you think theres a danger of it being removed or the ap going up then sign up now.
the ap going down isnt an issue as i said its a 10 minute job for the dealer.