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5 U.S. Code § 6336 - Restoration of transferred leave

The Office of Personnel Management shall establish procedures under which, except as provided in paragraph (2), any transferred leave remaining to the credit of a leave recipient when the medical emergency affecting the leave recipient terminates shall be restored on a prorated basis by transfer to the appropriate accounts of the respective leave donors.
(2) Nothing in paragraph (1) shall require the restoration of leave to a leave donor
if the amount of leave which would be restored to such donor would be less than 1 hour or any other shorter period of time which the Office may by regulation prescribe;
if such donor retires, dies, or is otherwise separated from service, before the date on which such restoration would otherwise be made; or
if such restoration is not administratively feasible, as determined under regulations prescribed by the Office.
(b) At the election of the leave donor, transferred annual leave restored to such leave donor under subsection (a) may be restored by—
crediting such leave to the leave donor’s annual leave account in the then current leave year;
crediting such leave to the leave donor’s annual leave account, effective as of the first day of the first leave year beginning after the date of the election; or
donating such leave in whole or part to another leave recipient; if a leave donor elects to donate only part of restored leave to another recipient, the donor may elect to have the remaining leave credited to the donor’s annual leave account in accordance with paragraph (1) or (2).
The Office shall prescribe regulations under which this section shall be applied in the case of an employee who is paid other than on the basis of biweekly pay periods.
Restorations of leave under this section shall be carried out in a manner consistent with regulations prescribed to carry out section 6334(c), if applicable.