If you have extra time on a case, tasks can be scheduled forward (tasks scheduled forward from today) or backward (remaining tasks scheduled backward from ship date) in thereschedule slider. There is also a system setting for forward/backward schedule, which determines the automatic scheduling in case entry.
Forward/Backward Schedule - Setting
If the ship/due date is extended, you can choose whether to schedule steps forward or backward from ship date in the Reschedule pop-out window
1) Scheduling forward from today:
2) Choose Schedule backward from ship date:
3) If some steps have already been completed, only remaining steps are rescheduled: