We own at Poly and bought knowing it was only studios and bought points knowing we were booking studios... I would imagine most poly owners did this, so I don't think you are going to have a zillion poly owners going for 1 and 2 bedrooms at the 11 month booking window causing a big issue IF this becomes the same association. Sure the 7 month window will be tricky if resale owners are allowed to book there, but the 7 month window is already tricky... depending on villa size and time of year it is hard to switch to other resorts.
It'll be interesting to see
point charts and number of villas in the new tower. I know everyone knocks poly 1 for being all studios, but studios seem to be the most problematic at other resorts... especially higher point resorts. Most buyers buy enough points for studios and those book first. I haven't paid much attention to Riviera, but I assume standard view studios go fast? If this is a new association, then I see the same issue happening. If this becomes part of poly 1, then at least there are a large number of studios. Yes, there will be competition for the shiny new studios, but there should be plenty of studios to go around. And at some point, ALL rooms stop being new and shiny.
As a current poly owner, I'm more concerned about the influx of guests IF they don't add decent food/pool options at the new tower. I'm remaining cautiously optimistic