We were planning on adding two days at Universal Orlando after WDW next week. We waited for a promo, and Universal started a “buy 2, get 3 free” promotion.
Even though we were only planning two days at the parks the promo was a game changer, as it changed the tickets from day specific tickets, to an 8 day window. So instead of paying weekend rates, we paid for Tuesday pricing. It saved $180 for the tickets, which we used to extend the Universal hotel for a day, so we could get an extra day and a half in the parks (with the extra days tickets already covered.
Even better (and luckier), when we extended the return date, the Delta vacations repricing came back $400 less expensive for the flights and the Swan days at the start of our trip!