Yes your question has been asked numerous times.
If you book at rack rate and a discount becomes available, you can modify your reservation online or call Disney and ask for the discount to be applied. The caveat is that discounts apply to SELECT room catergories, so you may have to upgrade your room or even switch resorts. Or you may get lucky and get a discount for your existing room.
(Disney will not automatically give your existing reservation a discount. You need to act.)
Disney releases discounts to fill unsold rooms. If everyone books at rack rate hoping for a future discount, Disney considers those rooms already booked and has less incentive to offer discounts.
Bottom line ~ if you want a particular resort room and are willing to pay rack rate, book now. Otherwise it is better to wait for the fall discount offer.
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