It could be a little manic I'm sure! Hopefully the MM+ support team have sent lots of people over to help for the next few weeks.
If the more technically savvy DIS folks are having the problems that they are, heaven help the one-time retiree visitors and their families who don't even have a computer, let alone a smart phone (reminds me of "car phone? We didn't even have a house phone..."). They are going to need so much hand-holding it is going to take forever.
Personally, I have felt for a while that they are trying to run before they can walk. The RFID-based KttW cards for door-locks, charging, park admission, etc. are really only just about stable enough to be considered as being out of their testing period. In a sensible world, that process should have been fully completed (including all park entrances converted to RFID readers) before even thinking about starting to issue Magic Bands. Then, once the Magic Band system was fully stable (and only then) would have been the right time to start testing FP+.
Piling three new technologies on top of each other is just asking for trouble IMHO. And I speak from an IT support background, having been involved in large roll-out programs.
Andre