If there are AP rates available for your dates of stay--you are able to book that rate. You may be asked to show the activated AP at the time of check-in. If you still haven't activated it, you will be asked to return to show the activated pass. Then again, the CM at the resort may not even ask for verification of the AP. Rest assured, however, you will be able to obtain an AP rate if they are available for your resort of choice and dates of stay.