I’m guessing the announcement of the Han Solo movie title and a Last Jedi teaser. Maybe Lucas will make a surprise appearance- in that case no OOT announcement.
Given the slightly scorched earth between Disney and George lately, a Dave Prowse appearance is more likely. 😉
Didn’t Prowse announce a year or two ago on his Facebook he was retiring from public appearances??
Don’t know about that, but he’s been “banned” from Celebration for quite some time. This would have been a good time to bury the hatchet and welcome him back.