My previous booking system used an incredible feature: clients, who were unable to find an appointment that suited them would add themselves to a waitlist, and as soon as a client would cancel this particular appointment type online, everyone on the waitlist for this appointment time would receive an automatic text message notification, which allowed them to snatch the appointment (first come, first serve ). it was such a time saver for me because as of right now, I’m the one maintaining a physical waitlist for clients because Phorest doesn’t offer this option.