1. Gym Settings -> Class Schedule / Timetable -> Schedule Settings
2. Set RSVP Allowed ____ Days prior to class field.
3. Set this to 1, to allow someone to book 24 hours in advance.
NOTE: It is a rolling limit. So, if this to 1 day, at 6:30am today, the 6:30am class for tomorrow will be come available to reserve.
You can also make these changes for an individual class.
1. Gym Settings -> Class Schedule -> Weekly Schedule
2. Tap the class to adjust
3. Tap "Between X days and X minutes before class"
4. Adjust the settings.
For example, for a 5am class, set RSVP Cut off to 480. This would require RSVP by 9pm the night before.