So Disney called me today saying that would be very busy on Monday, March 28th and would I be willing to move my FPs at MK to later in the day. In exchange for doing that, they gave me 3 anytime FPs at another park. She asked if I had any other questions, and I asked her why the MK wasn’t opening at 7 am that week, and then she said the posted hours are correct as of now but are always subject to change. It’s the first time I’ve ever had a call like that.
Someone else reported a similar experience here: