I seems like the discounts must be booked by Aug 14. what happens after that?
If a discount has an expiration date, then it expires. So, if you must book a reservation to get the discount discount by August 14, on August 15, it is no longer available. Depending on the timing and availability, Disney may extend a discount (rare), come out with an alternative but not as good of a discount (not as rare) or just move on without a discount (most likely) for those dates.
