We have booked through Ken and Denise 4 times now since May 2010, and my sister once. We traveled twice in the later part of May, once in early March, and once in late September. We always received the lower price within 60 days.
My sister and her DH traveled in 2010 in early November and was given the option of upgrading from a one bedroom to a 2 bedroom, which was a good choice for her as they rented a scooter in the parks from an outside service.
I think that the resort is very popular these days so it all depends. But if there is availability, Ken and Denise will do their best to get you the reduction in cost. I think they are great. We also stay DVC some trips, but I consider the Wyndham a very good choice. I especially like the 3 bedroom units, although with a big party 2 of the 2 bedroom units are a better deal.
I think most of these trips were not high season.