No one knows what will happen on extensions or at the end of the RTU. We can speculate but I see no evidence to suggest any option is more likely than another. I'd say it's about 50/50 whether any type of extension is offered or not and if it is, there are many variables. IMO the most likely possibility IF an extension is offered is for it to be tied to an additional retail purchase of some type. I'd agree that an OKW type of deal is dramatically unlikely, after that, who knows.
The main driver of extensions if DVC goes back into VWL and BCV is going to be the need for a broad base of MF payers.
If DVC adds 350 units to VWL in 2016, they are going to need a fifty year contract to sell anywhere near current prices.
So, what happens to MFs between 2042 and 2066? That's 24 yrs of MFs that will need to be spread over the entire resort. DVC can either offer an extension, or resell VWL/BCV in 2042 for another 50 yrs, until 2092...
It seems more prudent to put the entire resort on the same timeline.
Also, 2042 is going to start impacting the resale market. Not yet, but it's coming. Just look at the comparison here to BCV and BLT. DVC/Disney will have to address that because they can't afford to have their resale values to crash for several resorts at once. It'll drag down the whole machine. How much is BLT worth in 2035 if I can buy BCV for 35/point and book BLT at 7 months?
The current model absolutely depends on a brisk resale market. It's what makes DVC different from other timeshares.
I believe extension offers are coming, it's just a matter of when. I factored that into my purchase.