Any employee who is absent from duty without leave, or who fails to report after a leave of absence has expired, or fails to report after disapproval, revocation or cancellation of a leave of absence by the Commission, may be discharged therefor. An absence from duty without leave for ten consecutive days shall be deemed a resignation from the service. Upon notification of such ten days absence, the Commission shall enter the resignation of the employee. upon its records. If within ten days after such entry of resignation or, in the case of a discharge by reason of violation of this section within such time as the Commission may allow, the employee concerned satisfactorily explains such violation, the Commission may order his reinstatement.