10 U.S.C. § 12305

(a) Notwithstanding any other provision of law, during any period members of a reserve component are serving on active duty pursuant to an order to active duty under authority of section 12301, 12302, or 12304 of this title, the President may suspend any provision of law relating to promotion, retirement, or separation applicable to any member of the armed forces who the President determines is essential to the national security of the United States. (b) A suspension made under the authority of subsection (a) shall terminate (1) upon release from active duty of members of the reserve component ordered to active duty under the authority of section 12301, 12302, or 12304 of this title, as the case may be, or (2) at such time as the President determines the circumstances which required the action of ordering members of the reserve component to active duty no longer exist, which­ever is earlier. (c) Upon the termination of a suspension made under the authority of subsection (a) of a provision of law otherwise requiring the separation or retirement of officers on active duty because of age, length of service or length of service in grade, or failure of selection for promotion, the Secretary concerned shall extend by up to 90 days the otherwise required separation or retirement date of any officer covered by the suspended provision whose separation or retirement date, but for the suspension, would have been before the date of the termination of the suspension or within 90 days after the date of such termination.