Warrant officers: eligibility for promotion

§ 559. Warrant officers: eligibility for promotion Each permanent regular warrant officer shall be considered by a selection board for promotion to the next higher permanent regular warrant officer grade far enough in advance of the date upon which he will complete (1) three years of service in his permanent regular warrant officer grade, if he is in the grade of warrant officer, W–1, or (2) six years of service in his permanent regular warrant officer grade, if he is in the grade of chief warrant officer, W–2, or chief warrant officer, W–3, so that he may be promoted as of the day after the date on which he will complete that service.