Setting/automailsendoffset

The Trigger Time sets the time relative to the Trigger Event when the action should first trigger.

A positive Trigger Time value is after the event and a negative value is before the event.

To trigger an action before Check-in requires a negative Trigger Time value when using the Check-in Trigger Event.

A negative Trigger Time in combination with the Booking Trigger Event is not valid (trigger before booking is not possible).