I've heard rumors of a class as early as July, or as late as September. It's probably not set in stone. Could come earlier, could come later. Just depends on how they modify ASMs and how attrition factors in. With the seniority list coming to a dead stop for a while, there might be some junior guys hopping ship to go to places like Cathay and Emirates. That could speed things up.
As for re-interviewing, that's not really their style. I wouldn't worry about having to re-interview, even if the wait gets extended for a while. Once you're approved, I doubt they'll change it, because all approvals come directly from the VP level before you're even called and offered the job.