I did hear there were aged issues at the Poly, and updates halted a while ago. I am certain both a rebuilt Poly and a DVC Poly will happen in the next couple years. They need to redo the pools, add hot tubs, and have help off on updating, so the only logical thing is a total tear down and rebuild. Fancy pools, bigger seating for show, maybe some wedding stuff on the beach. Take up more room even to T and T, with wasted beautiful beach space.
They are building limited at GF, both for space, and exclusivity. I assume they will demolish the Poly, rebuild the paying side of Poly 1st, with plans inline for DVC. Once complete start the "DVC side", makes sence with time.
SSR will sell out this yr, it has in many months, AK can be the "discounted" DVC, may take just as long or longer to run out. ..GF will sell out within 3 years, assuming size is as small as shown. Assuming it will take time to get started on plans, building time, and they will complete the resort 1st; it will be up and running when GF is just about out of points, or at most a year away.

I wouldn't consider GF, and would prolly would aim for an inital buy in at the Poly. (If they added a hot tub.) There are just as many that felt that same way about BLT, and feel the same way about GF. So although there would be 1-2 yrs between them, they will not take as many buyers away from GF, even with the thoughts... Hey Poly is under construction maybe a DVC is coming, (they won't make it official for many many moons.) They need to figure out for sure what they are doing next, and this would make sense.