ADR Cancelation strategie

[goofytetreault]

Hello everyone, this is my first post but I have been reading for a while now. I will be staying at Fort Wilderness from the 11th to the 20th of august, and I would like to have breakfast at CRT on the 12th. We are four in my party and the only spot they have is for 6 people. Is it bad form the take that spot and upon arrival mentione that we'll only be 4, and also I'm on the dining plan, does that change anything?
Thanks a million