I was there on Wednesday, June 1st. Went to the late Jungle Book: Alive with Magic show and left the park around 11:05pm. Ended up waiting at least 20 minutes for a bus to Disney's Saratoga Springs Resort. However, that wait was due to a lack of a bus...not because there were tons of people.
Although, there seemed to be a lot of people at the various bus stops, it wasn't the madhouse that Magic Kingdom can be after Wishes. Just a guess, but none of the lines looked long enough to require more than one bus to clear. But, that would include standing room, too.