The City Manager may authorize unpaid leaves of absence up to a maximum duration of one year, except in the case of a leave necessitated by involuntary conscription or recall to duty in the Armed Forces of the United States, in which case the leave may be extended to cover the full period of conscription or recall. Upon expiration of such regularly approved leave, the employee shall be reinstated in the position held at the time leave was granted. Failure on the part of the employee to report for duty promptly at the expiration of such leave shall be regarded as a voluntary resignation. [Ord. 1306 § 52, 1968; Code 1970 § 2.42.380.]