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10 U.S. Code § 1206a - Reserve component members unable to perform duties when ordered to active duty: disability system processing

(a) Members Released From Active Duty Within 30 Days.—
A member of a reserve component who is ordered to active duty for a period of more than 30 days and is released from active duty within 30 days of commencing such period of active duty for a reason stated in subsection (b) shall be considered for all purposes under this chapter to have been serving under an order to active duty for a period of 30 days or less.
(b) Applicable Reasons for Release.—Subsection (a) applies in the case of a member released from active duty because of a failure to meet—
(1)
physical standards for retention due to a preexisting condition not aggravated during the period of active duty; or
(2)
medical or dental standards for deployment due to a preexisting condition not aggravated during the period of active duty.
(c) Savings Provision for Medical Care Provided While on Active Duty.—
Notwithstanding subsection (a), any benefit under chapter 55 of this title received by a member described in subsection (a) or a dependent of such member before or during the period of active duty shall not be subject to recoupment or otherwise affected.