I am guessing you checked and know your ADRs better than I do...

I definitely wouldn't lose any great ADRs, but it doesn't start until 8:30pm. And depending on which night in December it's 9:30pm or 10:30pm. So could you make it work, or ADRs during that 8:30pm time? Do you have park hoppers (if this is your issue)? That's not our EP day either. Christmas Eve works best, but IllumiNations @ 10:30pm, and didn't plan on being out that late. I have CP booked on 12/18 for 6:45pm, so will head over afterwards. Didn't plan on my day being that long, but we love the holiday version of IllumiNations and that's our anniversary day and we have a later start the next day. So I will make it work.