((a)) Except as provided in subsection (b), the period during which a person entitled to educational assistance under this chapter may use such person’s entitlement expires on the date the person is separated from the Selected Reserve.
((b))
((1)) In the case of a person—
((A)) who is separated from the Selected Reserve because of a disability which was not the result of the individual’s own willful misconduct incurred on or after the date on which such person became entitled to educational assistance under this chapter; or
((B)) who, on or after the date on which such person became entitled to educational assistance under this chapter ceases to be a member of the Selected Reserve during the period beginning on , and ending on , or the period beginning on , and ending on , by reason of the inactivation of the person’s unit of assignment or by reason of involuntarily ceasing to be designated as a member of the Selected Reserve pursuant to ,
((2)) The provisions of shall apply to the period of entitlement prescribed by subsection (a).
((3)) The provisions of shall apply to the period of entitlement prescribed by subsection (a) in the case of a disability incurred in or aggravated by service in the Selected Reserve.
((4)) In the case of a member of the Selected Reserve of the Ready Reserve who serves on active duty pursuant to an order to active duty issued under section 12301(a), 12301(d), 12301(g), 12302, 12304, 12304a, or 12304b of this title—
((A)) the period of such active duty service plus four months shall not be considered in determining the expiration date applicable to such member under subsection (a); and
((B)) the member may not be considered to have been separated from the Selected Reserve for the purposes of clause (2) of such subsection by reason of the commencement of such active duty service.
((5)) In any case in which the Secretary concerned determines that a person entitled to educational assistance under this chapter has been prevented from using such person’s entitlement due to an emergency situation, the Secretary concerned shall extend the period of entitlement prescribed in subsection (a) for a period equal to the number of months that the person was so prevented from using such entitlement, as determined by the Secretary.
((c)) In this section, the term “emergency situation” has the meaning given such term in .