Hi Liz, I own at a So California resort a couple of blocks from the beach and I just recently deposited a July 2009 week with RCI. This week seems to have the same trade power as it always has even when compared to other weeks that I've deposited a little bit earlier. I've also deposited one of these summer weeks as late as December and didn't really notice any difference in the trade power.
IMHO, I think the summer weeks on the southern California coast are valued quite high by RCI as long it is weeks 25-33.
Also, my resort is a VRI managed resort like Gaslamp and I've gotten a couple of super trades in the 30 day priority window to other VRI managed resorts within RCI.
Good luck with your trade!