At least 30 days before a selection board is convened under
section 611(a) of this title to recommend officers in a grade for promotion to the next higher grade, the Secretary concerned (1) shall notify in writing the officers eligible for consideration for promotion of the date on which the board is to convene and the name and date of rank of the junior officer, and of the senior officer, in the promotion zone as of the date of the notification, or (2) shall issue a general written notice to the armed force concerned regarding the convening of the board which shall include the convening date of the board and the name and date of rank of the junior officer, and of the senior officer, in the promotion zone as of the date of the notification.