The Update all Appointments and Online Meetings action will update all the appointments and online meetings associated with a scheduling request with the (newly selected) start time, as well as handling any cases where the scheduled users have changed - for example, when scheduling with a team, and picking a new time causes the appointment to be scheduled with a different team member.
TimeZest automatically tracks all appointments and online meetings created for a scheduling request, and will update all of them.
This action does not take any configuration, and is a critical action, which means that if it does not execute successfully, no further actions for the trigger will be executed.