239.—(1) Where any F374[…] military prisoner or man undergoing detention is for the time being in custody, whether service custody or civil custody, in any place or manner in which he might legally be kept in pursuance of this Act, the custody of such F374[…] prisoner or man shall not be deemed to be illegal by reason only of any informality or error in or as respects the order, warrant or other document, or the authority by or in pursuance whereof such F374[…] prisoner or man was brought into or is detained in such custody, and any such order, warrant or document may be amended accordingly.

(2) Where F374[…] a military prisoner or a man undergoing detention or a person who is subject to military law and charged with an offence is a prisoner or man in service custody and for the purpose of conveyance by sea F375[or air] is delivered on board a ship to the person in command of the ship F376[or aircraft] or to any other person on board the ship acting under the authority of the commander, the order of the military authority which authorises the prisoner or man to be conveyed by sea F375[or air] shall be a sufficient authority to such person, and to the person for the time being in command of the ship F376[or aircraft], to keep the said prisoner or man in custody and convey him in accordance with the order, and the prisoner or man while so kept shall be deemed to be kept in service custody.