When you make changes to your database or your schedule setup and then run a schedule, XPAC must determine what information needs to be recalculated. To speed up the scheduling process, schedule status files are used to store the record percentages at particular points in time. Depending on the changes that are made to your database or your schedule setup, XPAC will determine the latest schedule status that can be used in the recalculation of the schedule. This is called the scenario start point. You can manually change the scenario start point and force XPAC to recalculate the schedule from the beginning or some mid-point in the schedule.