I had all my ADRs booked for 4, in case one of my teens decided to come. She didn't, so we let them know at resort check in, and they were able to adjust the ADRs that would have been an issue. All that weren't, they left as is and told me just to let them know at the restaurant. We did, and it was fine the entire time. The ones I remember that needed to be adjusted were CRT, MBBQ, Hoop De Doo (I think), and PSB.