Time Periods for FML. 1) For FML purposes only, 12 workweeks means 12 workweeks in the calendar year (or 26 workweeks in the single 12-month leave period if the employee is taking FML as Military Caregiver Leave) for full-time employees. For employees who work less than full time or who work full time but on alternative work schedules, the number of working days shall be adjusted on a pro-rata basis.