What everyone says is true, but what harm can it do asking - say to Marriott that you want to buy an Aruba week from them but would only do do if they will allow you to enrol your post 2010 week(s)?
They will almost certainly say no, but they also won't want to miss out on a sale - their dilemma, not yours.
They will almost certainly say no, but they also won't want to miss out on a sale - their dilemma, not yours.