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3 U.S. Code § 453 - Election of proceeding

Not later than 90 days after a covered employee receives notice of the end of the period of mediation, but no sooner than 30 days after receipt of such notification, such covered employee may either—
(1)
file a complaint with the appropriate agency, as determined under section 454; or
(2)
file a civil action under section 1346(g) of title 28.