25 is the minimum for an add-on (50 if you want financing). So, I don't see why they wouldn't sell the points if they were available. The points DVC owns are no longer in contracts but are put back into the pool. They don't need to have a contract with themselves.
There is currently a waiting list for DVC owners who want to add-on at sold out resorts. We are on the OKW waitlist for an October use year, looking to buy 60 points. Our gude told us it would probably take a month or two before it came through.