As of right now, the only time a Prebook or rebook tracks is if the prebooking was done at check-out before collecting payment. It would be helpful to have the option to either go back to "view appointment" and then be able to select a prebook option to set a new prebooked appointment, OR to add a prebooking tick-box when setting an appointment through "new appointment". Lastly, either function should help track the prebook metric.