And if you don't have one, you may not be able to get in. We went on a relatively low crowd day and had a FP that we ended up not going to because of sleeping children... none left to reschedule to for later in the day, and then we got shut out of the standby line when we tried to get in later. Bit of a bummer. Hopefully we will get to see it in the fall! So if there is stuff you want to do more just get in line early, but if it is a top priority then I would FP it.