That isn't very plausible. The fact that a couple of AFOLs here don't like the truck stop isn't likely to affect their decisions. Moreover, the lead times for designing, producing, and distributing such a set are simply to long.
Maybe the release of 8403 and 8404 are simply delayed until August (which should also see the release of the train sets) and TLG has only shown sets until June (or so) at the NY Toy Fair.