If a class has a waiting list and a spot becomes available, a push notification is sent out to those on the waiting list informing them of the available spot. The notifications are sent out at 20-second intervals and in no particular order. The first person to book the spot gets it.
This approach is designed to quickly fill spots that often become available on short notice. Allowing everyone on the waitlist to respond in sequence would delay the process and risk leaving the spot unclaimed. To maximize your chances, act promptly when you receive the notification and book the class in the app.