My suggestion would be to book your dates ASAP. Don't wait till the month before, because the rooms reserved at the Ent rate do sell out. You can always cancel before the cancellation deadline, if your plans change. If your dates show up as Ent rates when they are released, you can call them, and they will change your reservation to the lower rate. If they don't come up, you can have a backup booking elsewhere-- or just keep them and you'll still get 15% online discount. Keep in mind you have to call IN HOUSE reservations to get the Ent rate; the HoJo national reservations line don't know squat about it.