When the jail of any other county or city has been adopted or designated under the provisions of §§ 53.1-74 and 53.1-76, any judge or magistrate authorized to issue temporary detention orders pursuant to §§ 37.2-809 through 37.2-813 of the adopting county or city shall have concurrent jurisdiction with those of the county or city wherein the adopted or designated jail is located, in proceedings under Chapter 8 (§ 37.2-800 et seq.) of Title 37.2, with respect to such persons as have been involuntarily admitted there from the adopting county or city. Such judge or magistrate may perform any such act or duty at such place as if such person was involuntarily admitted within the jurisdiction of the adopting county or city.