The available triggers for automatic Guest Messages are:

on confirmation Message is sent at the time a reservation is confirmed. This trigger can be configured for different bookning channels, by default the messages are only sent automatically to reservations made on hotel own website.

in X days after confirmation Message is sent a specified number of days after confirmation.

on update Message is sent when an update that changes the price is made to the reservation.

on cancellation Message is sent when reservation is Cancelled.

in X days after cancellation Message is sent a specified number of days after cancellation.

on extra room Message is sent if an additional room is added to the reservation.

on room cancellation Message is sent if a room is cancelled in the reservation.

on no-show Message is sent if a room becomes no-show.

in X days before arrival Message is sent a specified number before arrival. If this date is already passed the message will be sent on confirmation day.

on arrival day Message is sent on arrival day.

on check-in Message is sent when room is checked in.

on X day of stay Message is sent after the guest have stayed a specified number of days.

on room upgrade Message is sent if room is upgraded.

on room downgrade Message is sent if room is downgraded.

in X days before departure Message is sent s specified number of days before departure. If this date is already passed the message will be sent on confirmation date.

on departure day Message is sent on day of departure.

on check-out Message is sent on day of check-out.

in X days after departure Message is sent a specified number of days after departure.

in X days before invoice due date Message is sent in a specified number of days before the invoice due date. If this date is already passed the message will not be sent.

on invoice due date Message is sent on invoice due date.

in X days after invoice due date Message is sent in a specified number of days after the invoice due date.

in Y days(s) before each X-th day For a specified number of stay days the mail sent some days before. For example: "in 3 days(s) before each 30-th day" will send a mail 3 days before every 30 days the reservations have stayed.

on preliminary Message is sent at the time a reservation is made preliminary.

on payment Message is sent when a payment has been made (can also be when a payment link is paid for or an automatic charge is made).

on invoice Message is sent when a invoice has been created