promotion eligibility period
(4) In this subsection, the term “promotion eligibility period” means, with respect to an officer whose name is on a list of officers approved for promotion under section 624(a) of this title to a grade for which appointment is required by section 624(c) of this title to be made by and with the advice and consent of the Senate, the period beginning on the date on which the list is so approved and ending on the first day of the eighteenth month following the month during which the list is so approved.