Here is what I posted on the March thread when someone asked for suggestions:
It is hard to schedule the fp+'s. We were there in the first week of December and ended up using only a few of the original fp+ reservations. Test Track and TSMM were two of the ones that we made sure not to miss. Most of the time we decided not to go to the parks I had scheduled or not to go on the rides I had reserved. In fact, we didn't go on too many rides at all on that trip. We had the best time, though, maybe because it was Christmas and there was plenty to do there without worrying about the rides.
Here was/is my strategy:
1. reserve fp+'s for the most crowded rides, the ones they call the e-ticket rides, near the times you have an ADR
2. since most rides are walk-ons first thing in the morning, I made all my fp+'s for late afternoon and evening. When we used a fp+ in the evening, the fp line was empty. The fp return lines tend to be very long in the mornings because so many people schedule them for mornings.
3. I used the crowd calendars to get an idea of which parks to do that day, then scheduled the fp+ for that park
4. It is very easy to change times and attractions while you are in the park for most of the rides, except the e-ticket ones. Try not to miss your fp+ reservation for those few rides, because it will be hard to reschedule them. Most of the other rides are easy to reschedule. We were able to reschedule a fp+ for Buzz Lightyear and walk on the ride five minutes later, bypassing a 25 minute standby line.
Other things I learned:
1. if a ride that you had a fp+ for goes down, you can get in the fp return line for another ride, just tell the CM that your original ride is down. We had a fp+ for BMRR which was down when we went to it. We were able to ride Haunted Mansion and still reschedule the BMRR for another ride.
2. If you miss a fp+ reservation you can reschedule it for later that day. You don't lose your chance to have three fp+ reservations in a day. They do expire the next day, though, so you have to use them that day.
3. If you decide to cancel your fp+'s at one park in order to go to another park at the last minute, while riding the bus in, or something like that, you might have to wait until you are in the park before you can schedule new ones. We cancelled our HS fp+'s while riding the boat to MK. The app wouldn't let me make fp+'s for MK until after I had gotten into the park.
If the app doesn't seem to want to do what you want, like schedule a fp+, just shut it down, wait awhile, then go back in. Sometimes databases need to reset or record the data. I saved myself a lot of time and worry by just closing down the program for a short time rather than trying to fight with it. My MB suddenly refused to work on a purchase and to open our resort room. I just waited a few hours and then it magically started to work again. .
Although... the pampering of the lounge would be nice... ah! I just can't decide!!!
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