When you book it they will ask if you are on the dining plan. They 'should' not charge yoru CC since you are on the dining plan but they will take a CC as that is their policy to have a CC on file for no shows. You must cancel within 48 hours or your CC on file will be charged.
Now, some CM make the mistake of charging you even if you are on the DDP so if that happens, just call back and ask for a credit.