This subtitle does not affect: the authority granted under Subtitles 1 and 7 of this title; or a work release program established under Subtitles 1 and 7 of this title. With the approval of the Secretary, a county may convert a work release program established under Subtitles 1 and 7 of this title into a center that is subject to this subtitle. The Secretary shall adopt regulations for the conversion of a work release program into a center.