Under regulations prescribed by the Secretary concerned, an accused who has been sentenced by a court-martial may be required to take leave pending completion of action under this subchapter if the sentence includes an unsuspended dismissal or an unsuspended dishonorable or bad-conduct discharge. The accused may be required to begin such leave on the date of the entry of judgment under section 860c of this title (article 60c) or at any time after such date, and such leave may be continued until the date on which action under this subchapter is completed or may be terminated at any earlier time.