After, would be unfair to the people going to the tournament.
You could say that the tourney wouldn't use the patch anyway as it would come to late, but then the people who are going to the tournament can't play online for a week to practice, and that would suck for them.(well for the handful of them that use online for MU experience anyway)
But in the grand scheme of things, those players ultimately don't matter much, so NRS can do w/e they want. But I doubt the patch is coming tomorrow anyway.
