In any fiscal year, the total number of officers selected for retirement or separation under subsection (a) plus the number of officers retired for age may not exceed the whole number nearest 4 percent of the total number of officers authorized to be on the active list, except as otherwise provided by law.
A retirement or separation under subsection (a) shall take effect on the first day of the sixth month beginning after the date on which the Secretary approves the retirement or separation, except that if the officer concerned requests an earlier retirement or separation date, the date shall be as determined by the Secretary.
If the Secretary determines that the evaluation of the medical condition of an officer requires hospitalization or medical observation that cannot be completed with confidence in a manner consistent with the officer’s well-being before the date on which the officer would otherwise be required to retire or be separated under this section, the Secretary may defer the retirement or separation of the officer.