(a) A person who would otherwise be required to be transferred to a reserve component under section 651 of this title or under the Military Selective Service Act (50 U.S.C. 3801 et seq.), is entitled, if he is qualified and accepted, to be appointed as an officer of any armed force that he chooses and to participate in the programs authorized for that armed force. However, unless the two Secretaries concerned consent, he may not be appointed as a Reserve of an armed force other than that from which he is transferred. All periods of his participation shall be credited against the total period of service required of him under section 651 of this title or under the Military Selective Service Act (50 U.S.C. 3801 et seq.). However, no period may be credited more than once.
(b) A person covered by subsection (a) shall perform the rest of his required term of service in the armed force in which he is so appointed or in any other armed force in which he is later appointed or enlisted.
(c) This section does not change any term of service under an appointment, enlistment, or agreement, including an agreement made before or at the time when the member entered upon a program authorized by an armed force.
Structure US Code
Subtitle E— Reserve Components
CHAPTER 1205— APPOINTMENT OF RESERVE OFFICERS
§ 12201. Reserve officers: qualifications for appointment
§ 12202. Commissioned officer grades
§ 12203. Commissioned officers: appointment, how made; term
§ 12204. Commissioned officers: original appointment; limitation
§ 12205. Commissioned officers: appointment; educational requirement
§ 12206. Commissioned officers: appointment of former commissioned officers
§ 12207. Commissioned officers: service credit upon original appointment
§ 12208. Officers: appointment upon transfer
§ 12209. Officer candidates: enlisted Reserves
§ 12210. Attending Physician to the Congress: reserve grade
§ 12211. Officers: Army National Guard of the United States
§ 12212. Officers: Air National Guard of the United States
§ 12213. Officers; Army Reserve: transfer from Army National Guard of the United States
§ 12214. Officers; Air Force Reserve: transfer from Air National Guard of the United States
§ 12215. Commissioned officers: reserve grade of adjutants general and assistant adjutants general