I also prepaid for a plane "Not a Jet" that was new or prerelease with a projected 4 week ship date and waited over a year for it and when it became available it showed up as sold out and I got dragged thru a knothole backwards to get mine as the retailers were getting theirs first, they tried to put me on the back burner but with enough persistance I finally managed to get my bird, but the message was very clear, never order anything that isn't already in stock and you can verify that one is earmarked for delivery to you.
wholesalers will always satisfy their larger orders first even if that order came in after yours and it means kicking your order to the backburner to wait another 16 weeks for the next container/s to show up and clear customs etc and thats only if and when the big players orders are satisfied first