law: 151. Commencement of sentence.
  (1) Subject to the provisions of 1[sub-sections (2) and (3)] every term of imprisonment or detention awarded in pursuance of this Act shall be reckoned as commencing on the day on which the sentence was awarded.
  (2) Where by reason of a ship being at sea or off a place at which there is no proper prison or naval detention quarters, a sentence of imprisonment or detention, as the case may be, cannot be duly executed, then subject as hereinafter mentioned, an offender under the sentence of imprisonment or detention, as the case may be, may be sent with all reasonable speed to some place at which there is a proper prison or naval detention quarters or in the case of an offender under sentence of detention to some place at which there are some naval detention quarters in which the sentence can be duly executed; and on arrival there, the offender shall undergo his sentence in like manner as if the date of such arrival were the day on which the sentence was awarded and notwithstanding that in the meanwhile he has returned to his duty or become entitled to his discharge; and the term of imprisonment or detention, as the case may be, shall be reckoned accordingly, subject however to the deduction of any time during which he has been kept in confinement in respect of the said offence.
  2[(3) Whenever any offender is sentenced by a court-martial to a term of imprisonment, in pursuance of this Act, not being imprisonment in default of payment of fine, the period spent by him in civil or naval 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 terms of imprisonment imposed upon him, and the liability of such offender to undergo imprisonment on such order of sentence shall be restricted to the remainder, if any, of the term of imprisonment imposed upon him.]