169-A. Period of custody undergone by the officer or person to be set off against the imprisonment. -When a person or officer subject to this Act is sentenced by a court-martial to a term of imprisonment, not being an imprisonment in default of payment of fine, the period spent by him in civil or military custody during investigation, inquiry or trial of the same case, and before the date of order of such sentence, shall be set-off against the term of imprisonment imposed upon him, and the liability of such person or officer to undergo imprisonment on such order of sentence shall be restricted to the remainder, if any, of the term of imprisonment imposed upon him). | 