Some dude reported that he called J Crew and asked about these orders. They said that the orders would be fulfilled.
(Although the first rule of the hot deal is to never call customer service.)
Also, based on past experience with these J Crew coupons, they didn't cancel orders once they were accepted.
I guess this case is a little different since there is such a long time before they're expected to ship.
J Crew has allowed 25% off from time to time.
I think they just don't like people to run wild on it maybe.