I have ORD - PTY booked for the end of the month. My res was showing the 737 Max up until a few days ago...now it looks like they have switched to the 787-800. Why would they revert back to the old model so far in advance? Very annoying, because I would not have sprung for business class on the old planes. I know equip changes sometimes happen at the last moment, but this seems more deliberate.