I have set up a specific schedule upon which patients will arrive into my model clinic based upon their appointment time. The appointments are not a uniform length or time distribution and I only want them to be seen until the next appointment time. (ex. If the next appointment is 30 min later that is how long the process time should be, but if the next appointment is 15 min later then i want the process time to be 15 min). Is it possible to set something like this up for one of the steps in the track to have their process time be variable and contingent upon the appointment schedule?