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5 U.S. Code § 6368 - Termination of medical emergency

(a) The medical emergency affecting a leave recipient shall, for purposes of this subchapter, be considered to have terminated on the date as of which—
the leave recipient notifies the Leave Bank Board in writing, that the medical emergency no longer exists;
the Leave Bank Board of such leave recipient determines, after written notice and opportunity for the leave recipient (or, if appropriate, another person acting on behalf of the leave recipient) to answer orally or in writing, that the medical emergency no longer exists; or
the leave recipient is separated from service.
The Leave Bank Board of a recipient shall, consistent with guidelines prescribed by the Office of Personnel Management, establish procedures to ensure that a leave recipient is not permitted to use or receive any transferred leave under this subchapter after the medical emergency terminates.
Nothing in section 5551, 5552, or 6306 shall apply with respect to any annual leave transferred to a leave recipient under this subchapter.