My guess, based on last year's terms, is that AP-holders would have to buy those one-day passes again. Campsites (but not cabins) are excluded from the promotion. I'm not sure whether suites are...I don't remember what happened last year for those.
Regarding the impact DDP has on ADR availability: I think it's pretty obvious. It's very difficult to get into Le Cellier these days without a reservation more than 90 days out - and for the more popular dining times it's more like 150 to 180. It'd be interesting to see, with all the changes over the past year, a seat at Cinderella's Royal Table is still the most difficult to get in WDW. I'd be surprised if a 6 pm dinner reservation at Le Cellier isn't almost as hard.
In case anyone's interested - the way we figure these things out is by calling Disney Dining over and over again, day after day, to ask for tables at specific restaurants on certain days and times. It allows us to track how fast certain restaurants fill up. It also helps if you have your phone service via cable modem, to avoid long-distance charges.
Len