Book your first three fast passes online (or in the Disney App) 60 days ahead if you are staying on site and 20 days ahead if you are offsite. At 30 days they go real fast so if you wait until 29, you will miss out on the most popular rides. Once you have used all three fast passes in a day, you may book one at a time using your app or kiosks throughout the park. I used the app and booked my next as soon as I joined the line for the last. But pay attention because if a ride shuts down you can use your fast pass at all the rides except the dwarf ride.
the best thing is to approach the guys from the attractions and the questions I recommend that you do it as early as possible. I think you can also do it by the application my disney experience
As soon as possible
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