Buy your boat when you find one that you feel is right for you, if that's this fall fine, if not, whenever. Given the storgae and carrying costs you don't necessarily make out by buying in the Fall...buy when you have the right boat.
Given the size boat you are interested in, I'd strongly recommend buying one of a quality, classic 30 footer: Pearson, Tartan, Cataline, Cal, Ericson, Sabre all made nice boats in mid-70-80s that will provide a lot more boat, and a better boat, than the two newer alternatives you are looking at. With the older 30 for the same money you should be able to find one that has been upgraded, don't try to buy cheap, you'll make out better fi you pay a premium for a premium example.
Certified...in several regards...