(a) Any aggrieved party may obtain judicial review of a final action of the Secretary or the Board on any grievance in the district courts of the United States in accordance with the standards set forth in chapter 7 of title 5, if the request for judicial review is filed not later than 180 days after the final action of the Secretary or the Board (or in the case of an aggrieved party who is posted abroad at the time of the final action of the Secretary or the Board, if the request for judicial review is filed not later than 180 days after the aggrieved party’s return to the United States). Section 706 of title 5 shall apply without limitation or exception. This subsection shall not apply to any grievance with respect to which subsection (b) applies.

(b)(1) For purposes of this subsection, the term “aggrieved party” means a grievant.

(2) With respect to a grievance based on an alleged violation of a law, rule, regulation, or policy directive referred to in section 4131(a)(1)(H) of this title, judicial review of whether the act, omission, or condition that is the basis of the grievance violates such law, rule, regulation, or policy directive may be obtained by an aggrieved party only if such party commences a civil action, not later than 90 days after such party receives notice of the final action of the Secretary or the Board, in an appropriate district court of the United States for de novo review.