Of course they'd be within their rights to do so, but I think they'll just leave it. It's not only unprecedented for SE to revoke licences in event of misprice, it'd also be tons of work for no profit and bad PR. Not worth the effort IMO, especially for digital goods.Sony and Square are well within their rights to revoke the licenses and refund the orders. I agree that it could lead to more season pass and DLC purchases, but possibly not enough to offset however many units they've sold at a massive 80% off.
It's not like they're Amazon sending out physical boxes.