Never mind June 3rd, the thing we need to know is what's happening on May 27th at 8 PM. If we're getting an episode of Super that won't be on Toonami that night, it HAS to be on Toonami SOMETIME, and the best way to accomplish that (ratings be damned) would be a Super Power Hour at 11 PM on June 3rd.
Also, something interesting is happening with Hunter x Hunter: it's on episode 52 next week (5/20/17). Could it be that it takes a small break starting June 3rd in favor of another show, then comes back later in a better timeslot?