PUBLIC LAWS-CH. 512 -AUG. 7,1947 41 Stat. 762 . Retirement. Retirement. Officers of Medical Corps. Professors of U. S. Military Academy. Retired grade and pay. names appear upon the promotion list concerned, and the names of officers of any component of the Army of the United States serving on extended active duty in grades above lieutenant colonel who have demonstrated by actual and extended duty in the branch, arm, or service concerned, or on similar duty, that they are qualified for such assignment. From among the officers named for consideration the board shall select and recommend the prescribed number. From among those recommended by such board, the President may appoint an officer in the position concerned. If the President declines to appoint any of those so recommended or if those he may nominate cannot be appointed because of advice by the Senate, the Secretary of War shall convene a board to select and recommend additional officers in accordance with the procedure heretofore prescribed. Officers who are recommended and who are not appointed shall be deemed not to have been recommended but this shall in no way prejudice their eligi- bility for selection and recommendation for the grade of major gen- eral or brigadier general under the provisions of sections 511 and 512 of this title. (c) Section 4c of the National Defense Act, as amended (10 U. S . C . 8, 482a, 6, 1026, 27, 532, 28, 29, 533, 13, 534), is further amended by deleting therefrom all words except the words: "Any officer who shall have served four years as chief or assistant chief of a branch or as commanding general of the General Headquarters Air Force and who may subsequently be retired, shall be retired with the rank, pay, and allowances authorized by law for the highest grade held by him as such chief, assistant chief, or commanding general: Provided, That this provision shall not reduce the rank, pay, or allowances with which such officer would otherwise be entitled to retire." REGULAR ARMY OFFICERS-ELIMINATION FROM ACTIVE LIST-MANDATORY RETIREMENT OR SEPARATION SEC. 514. (a) (1) After that date which is six months after the date of enactment of this Act, unless provided otherwise by some provision of law, each commissioned officer of the Regular Army (other than a professor of the United States Military Academy), who is not retired or separated at an earlier date under applicable provisions of law, shall, if in the permanent grade of brigadier general or in any perma- nent grade below that of brigadier general, be retired on that date upon which he attains the age of sixty years; and, if in the permanent grade of major general, be retired on that date upon which he attains the age of sixty-two years: Provided, That officers holding appoint- ments on the date of enactment of this Act as chiefs and assistant chiefs of services shall not by reason of the enactment of this section be retired while so serving until age sixty-four years is reached if serving with the rank of major general or until age sixty-two years is reached if serving with the rank of brigadier general: Provided further, That the provisions of this paragraph requiring retirement at age sixty years and sixty-two years shall not become effective for officers of the Medical Corps until one year after date of enactment of this Act. (2) Each professor of the United States Military Academy, who is not retired or separated at an earlier date under applicable provisions of law, shall be retired on that date upon which he attains the age of sixty-four years. (3) Each commissioned officer of the Regular Army who is here- after retired by reason of reaching the age of sixty years, sixty-two years, or sixty-four years, as the case may be, shall be retired in the permanent grade held at time of retirement and shall receive retired pay computed on the basis provided in subsection (e) (1) of this 902 [61 STAT.