Space Mountain, BTMRR, and Haunted Mansion.
I'm going the same week and I made some FP reservations earlier today. Most things gave the usual one hour window but an 8:25 Fantasmic reservation states: Arrive between 8:25-8:45. The show starts at 9:00 so this makes sense but I don't remember it being designated this way on past trips.
I also booked two of the three that the OP mentions- BTMRR and HH, both of those are an hour as usual.
It was a glitch. I had booked Tower of Terror with a return time of 8-8:30 pm but did not think anything of it because I did not check park hours and assumed the park closed at 8:30.I went to book some last minute fastpasses for our 4th of July trip and it says the arrival window is now the first 30 minutes of the hour window. When did that change happen? Not sure I'm a huge fan.
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