We arrived right at 9:00 AM (opens at 9:00 AM) on a Saturday. Wow, the line to get in was long, but it was super quick, and there were plenty of staff to guide us. Just show the app voucher (via your phone), the process is quick, and then you're given a wristband with your money pre-loaded (I paid with a debit card). That's it, we went in and had fun.