((a)) Subject to subsections (b), (c), and (d) and to section 4304, any person whose absence from a position of employment is necessitated by reason of service in the uniformed services shall be entitled to the reemployment rights and benefits and other employment benefits of this chapter if—

((1)) the person (or an appropriate officer of the uniformed service in which such service is performed) has given advance written or verbal notice of such service to such person’s employer;

((2)) the cumulative length of the absence and of all previous absences from a position of employment with that employer by reason of service in the uniformed services does not exceed five years; and

((3)) except as provided in subsection (f), the person reports to, or submits an application for reemployment to, such employer in accordance with the provisions of subsection (e).

((b))

((1)) No notice is required under subsection (a)(1) if the giving of such notice is precluded by military necessity or, under all of the relevant circumstances, the giving of such notice is otherwise impossible or unreasonable.

((2)) A determination of military necessity for purposes of paragraph (1) shall be made—

((A)) except as provided in subparagraphs (B) and (C), pursuant to regulations prescribed by the Secretary of Defense;

((B)) for persons performing service to the Federal Emergency Management Agency under section 327 of the Robert T. Stafford Disaster Relief and Emergency Assistance Act () and as intermittent personnel under section 306(b)(1) of such Act (), by the Administrator of the Federal Emergency Management Agency as described in sections 327(j)(2) and 306(d)(2) of such Act ( and 5149(d)(2)), respectively; or

((C)) for intermittent disaster-response appointees of the National Disaster Medical System, by the Secretary of Health and Human Services as described in section 2812(d)(3)(B) of the Public Health Service Act ().

((3)) A determination of military necessity under paragraph (1) shall not be subject to judicial review.

((c)) Subsection (a) shall apply to a person who is absent from a position of employment by reason of service in the uniformed services if such person’s cumulative period of service in the uniformed services, with respect to the employer relationship for which a person seeks reemployment, does not exceed five years, except that any such period of service shall not include any service—

((1)) that is required, beyond five years, to complete an initial period of obligated service;

((2)) during which such person was unable to obtain orders releasing such person from a period of service in the uniformed services before the expiration of such five-year period and such inability was through no fault of such person;

((3)) performed as required pursuant to , under section 502(a) or 503 of title 32, or to fulfill additional training requirements determined and certified in writing by the Secretary concerned, to be necessary for professional development, or for completion of skill training or retraining; or

((4)) performed by a member of a uniformed service who is—

((A)) ordered to or retained on active duty under section 688, 12301(a), 12301(g), 12302, 12304, 12304a, 12304b, or 12305 of title 10 or under section 331, 332, 359, 360, 367, or 712  of title 14;

((B)) ordered to or retained on active duty (other than for training) under any provision of law because of a war or national emergency declared by the President or the Congress, as determined by the Secretary concerned;

((C)) ordered to active duty (other than for training) in support, as determined by the Secretary concerned, of an operational mission for which personnel have been ordered to active duty under ;

((D)) ordered to active duty in support, as determined by the Secretary concerned, of a critical mission or requirement of the uniformed services;

((E)) called into Federal service as a member of the National Guard under chapter 15  of title 10 or under ; or

((F)) ordered to full-time National Guard duty (other than for training) under when authorized by the President or the Secretary of Defense for the purpose of responding to a national emergency declared by the President and supported by Federal funds, as determined by the Secretary concerned.

((d))

((1)) An employer is not required to reemploy a person under this chapter if—

((A)) the employer’s circumstances have so changed as to make such reemployment impossible or unreasonable;

((B)) in the case of a person entitled to reemployment under subsection (a)(3), (a)(4), or (b)(2)(B) of section 4313, such employment would impose an undue hardship on the employer; or

((C)) the employment from which the person leaves to serve in the uniformed services is for a brief, nonrecurrent period and there is no reasonable expectation that such employment will continue indefinitely or for a significant period.

((2)) In any proceeding involving an issue of whether—

((A)) any reemployment referred to in paragraph (1) is impossible or unreasonable because of a change in an employer’s circumstances,

((B)) any accommodation, training, or effort referred to in subsection (a)(3), (a)(4), or (b)(2)(B) of section 4313 would impose an undue hardship on the employer, or

((C)) the employment referred to in paragraph (1)(C) is for a brief, nonrecurrent period and there is no reasonable expectation that such employment will continue indefinitely or for a significant period,

((e))

((1)) Subject to paragraph (2), a person referred to in subsection (a) shall, upon the completion of a period of service in the uniformed services, notify the employer referred to in such subsection of the person’s intent to return to a position of employment with such employer as follows:

((A)) In the case of a person whose period of service in the uniformed services was less than 31 days, by reporting to the employer—

((i)) not later than the beginning of the first full regularly scheduled work period on the first full calendar day following the completion of the period of service and the expiration of eight hours after a period allowing for the safe transportation of the person from the place of that service to the person’s residence; or

((ii)) as soon as possible after the expiration of the eight-hour period referred to in clause (i), if reporting within the period referred to in such clause is impossible or unreasonable through no fault of the person.

((B)) In the case of a person who is absent from a position of employment for a period of any length for the purposes of an examination to determine the person’s fitness to perform service in the uniformed services, by reporting in the manner and time referred to in subparagraph (A).

((C)) In the case of a person whose period of service in the uniformed services was for more than 30 days but less than 181 days, by submitting an application for reemployment with the employer not later than 14 days after the completion of the period of service or if submitting such application within such period is impossible or unreasonable through no fault of the person, the next first full calendar day when submission of such application becomes possible.

((D)) In the case of a person whose period of service in the uniformed services was for more than 180 days, by submitting an application for reemployment with the employer not later than 90 days after the completion of the period of service.

((2))

((A)) A person who is hospitalized for, or convalescing from, an illness or injury incurred in, or aggravated during, the performance of service in the uniformed services shall, at the end of the period that is necessary for the person to recover from such illness or injury, report to the person’s employer (in the case of a person described in subparagraph (A) or (B) of paragraph (1)) or submit an application for reemployment with such employer (in the case of a person described in subparagraph (C) or (D) of such paragraph). Except as provided in subparagraph (B), such period of recovery may not exceed two years.

((B)) Such two-year period shall be extended by the minimum time required to accommodate the circumstances beyond such person’s control which make reporting within the period specified in subparagraph (A) impossible or unreasonable.

((3)) A person who fails to report or apply for employment or reemployment within the appropriate period specified in this subsection shall not automatically forfeit such person’s entitlement to the rights and benefits referred to in subsection (a) but shall be subject to the conduct rules, established policy, and general practices of the employer pertaining to explanations and discipline with respect to absence from scheduled work.

((f))

((1)) A person who submits an application for reemployment in accordance with subparagraph (C) or (D) of subsection (e)(1) or subsection (e)(2) shall provide to the person’s employer (upon the request of such employer) documentation to establish that—

((A)) the person’s application is timely;

((B)) the person has not exceeded the service limitations set forth in subsection (a)(2) (except as permitted under subsection (c)); and

((C)) the person’s entitlement to the benefits under this chapter has not been terminated pursuant to section 4304.

((2)) Documentation of any matter referred to in paragraph (1) that satisfies regulations prescribed by the Secretary shall satisfy the documentation requirements in such paragraph.

((3))

((A)) Except as provided in subparagraph (B), the failure of a person to provide documentation that satisfies regulations prescribed pursuant to paragraph (2) shall not be a basis for denying reemployment in accordance with the provisions of this chapter if the failure occurs because such documentation does not exist or is not readily available at the time of the request of the employer. If, after such reemployment, documentation becomes available that establishes that such person does not meet one or more of the requirements referred to in subparagraphs (A), (B), and (C) of paragraph (1), the employer of such person may terminate the employment of the person and the provision of any rights or benefits afforded the person under this chapter.

((B)) An employer who reemploys a person absent from a position of employment for more than 90 days may require that the person provide the employer with the documentation referred to in subparagraph (A) before beginning to treat the person as not having incurred a break in service for pension purposes under section 4318(a)(2)(A).

((4)) An employer may not delay or attempt to defeat a reemployment obligation by demanding documentation that does not then exist or is not then readily available.

((g)) The right of a person to reemployment under this section shall not entitle such person to retention, preference, or displacement rights over any person with a superior claim under the provisions of title 5, United States Code, relating to veterans and other preference eligibles.

((h)) In any determination of a person’s entitlement to protection under this chapter, the timing, frequency, and duration of the person’s training or service, or the nature of such training or service (including voluntary service) in the uniformed services, shall not be a basis for denying protection of this chapter if the service does not exceed the limitations set forth in subsection (c) and the notice requirements established in subsection (a)(1) and the notification requirements established in subsection (e) are met.