"Sec. 10-A. The provisions of any law to the contrary notwithstanding, all enlistments of enlisted men serving with the Philippine Expeditionary Force shall continue in force as long as the Philippines continues to maintain the said force overseas, unless sooner terminated by the President pursuant to any approved sentence of a court-martial: Provided, That nothing herein shall operate to prevent the reenlistment of an enlisted man in the Armed Forces of the Philippines on the date of his last enlistment.