promotion zone
(1) The term “promotion zone” means a promotion eligibility category consisting of officers on a warrant officer active-duty list in the same grade (or the same grade and competitive category) who— (A) in the case of grades below chief warrant officer, W–5, have neither (i) failed of selection for promotion to the next higher grade, nor (ii) been removed from a list of warrant officers recommended for promotion to that grade (other than after having been placed on that list after a selection from below the promotion zone); and (B) are senior to the warrant officer designated by the Secretary concerned to be the junior warrant officer in the promotion zone eligible for promotion to the next higher grade.