I just returned from a trip last week at BC and received my first Bounceback offer after many visits to WDW. It was available for rooms through mid-December. I used it for my return trip in October for F&W. I will say that the majority of the rooms available for the bounceback rate were the higher priced rooms - with views, with club level/concierge, and suites. No standard rooms seemed to be available at any of the Epcot resorts for the special bounceback rate.
I can say that the AP and regular room discount that's going on now has the same issue. Although I've found that the closer it gets to your travel date, the more rooms open up at different price levels. I had a WL room booked last May during an AP discount time, but Poly was not offering any rooms at the special rate. I checked every single day until one day - Poly was suddenly available for $244 a night. Worth switching over for me. Keep checking!