My experience is that once you pick three attractions at 60 days, when events that are made available later (like the Electric Parade) never show up as something you can swap into. I have set up attractions for the same time frame and tried to swapping, but it never shows. I was able to cancel One persons FP+ for the day, rebook them with the Electric Parade and the copy to everyone else. However, that's was not able to get the same times for the other two attractions. This seems to be a bug in the system and favors people who wait until it is available to make FP+ for any of those later released parades / fireworks. Any one else having better luck?