Next question: If I buy an AP and link it to MDE and it's not activated yet, can I use it to get an AP discount on a room reservation? Or does the AP have to be activated in order to reserve a room? Back in ye olden days, I used to buy and activate my AP the day I got to WDW, but I would book the AP discount room reservation months in advance. But that was eons ago.
Just wanted to add that if you are willing to call you will be able to get an AP room rate without actually having the AP as long as you will have it at the time of your stay. So you could buy the 10 day tickets with the plan up upgrading and still get the AP rate room. I just did this for a trip in January.