Use of Excess. Employees who have more than one year’s vacation leave entitlement to their credit must obtain written authorization by September 15th of each year, from the Director of their branch, to carry over their excess vacation leave to the following year. If the Director denies the carry-over of the excess vacation leave into the following year, requests for the use of such excess between September 15th and December 31st of that year shall not be unreasonably denied. Should the employee not arrange the use of this excess vacation leave by September 30th, the Director may schedule its use. Should the Director not be able to allow the use of this excess between September 15th and December 31st, the employee shall carry this excess leave over into the following year.