when you get the dining plan. You must pay rack rate for the room and purchase at least 1 day tickets.
So if you have an AP, you will not be able to take advantage of any AP room discount if you want the dining plan. You'd have to pay rack, purchase 1 day tickets (which we all believe you can hold and put against your AP renewal price) and then purchase the dining plan. You have to determine if the loss of the AP discount plus the price of the dining plan would be less than you would eat, taking into account any discount you can get with the DDE card.