This can be changed, but it is a bit of a hassle. Of course usually the savings is worth it. When you call to change the rate to a code rate the original reservation will not be the one that is changed. You will have to book a new reservation and then cancel the old one. I have had to do this a few times. The room you booked to begin with is through WDTC (disney club reservations always go through this and are treated as a package even if it is room only) and the code rate will be through CRO so they can't just switch them. Do not cancel the original reservation until you have the new one secured since you don't want to be left out in the cold and have to begin planning again. Remember that CRO with an AP code is the room only price--no park admission, but with AP's you wouldn't need that anyway.
