Click n the "+ Schedule Personnel" button to open the window.
The Save and Add Another button will keep the Unit and Schedule intact, to facilitate quickly adding all the personnel assigned to the unit for the given date range.

Block: (Legacy data, not required)
Unit: The unit that the schedule belongs to. Loads the schedule list below.
Schedule: The list of schedules associated with the unit
Date Range: The date that the personnel will appear on the schedule.
Employee: The name of the person who will be added to the schedule.
Role: The role this person will perform on the schedule, e.g. "Technician #1" or "Faculty #4"