ADRs without knowing park hours?

[Smiling Cheshire Cat]

We arrive on November 29th and can make ADRs on August 31st. Since December hours will not be out until Sept. 1st, will CM be able to help me make ADRs for December? I'm especially concerned about booking the Fantasmic Dinner Package since I can't see any pattern of when they are showing Fantasmic now that it's no longer on every night and we are not going to have park hoppers.
Thanks for the help!