Timing of Leaves. Courteous scheduling of discretionary leaves contributes to workplace harmony and conserves District revenues. Employees are entitled to make full use of all available leaves as circumstances dictate. However, employees are requested to schedule periods of discretionary leave (i.e., sick leave for elective surgery, personal necessity leave) during periods of time when their absence will result in minimal disruption for the remaining staff or will not require the employment of a substitute to replace the employee.