129. (1) Where a finding of guilty by a court martial, which has been confirmed, or which does not require confirmation, is found for any reason to be invalid or cannot be supported by the evidence, the authority which would have had power under section 143 to commute the punishment awarded by the sentence, if the finding had been valid, may substitute a new finding, if the new finding could have validly been made by the court martial on the charge and if it appears that the court martial must have been satisfied of the facts establishing the offence specified or involved in the new finding, and may pass a sentence for the said offence. (2) Where a sentence passed by a court martial which has been confirmed, or which does not require confirmation, not being a sentence passed in pursuance of a new finding substituted under sub-section (1) is found for any reason to be invalid, the authority referred to in the sub-section may pass a valid sentence. (3) The punishment awarded by a sentence passed under sub-section (1) or sub-section (2) shall not be higher in the scale of punishments than, or in excess of the punishment awarded by, the sentence for which a new sentence is substituted under this section. (4) For the purposes of this Act, any finding or sentence substituted in accordance with this section for the finding or sentence of a court martial, and any sentence imposed for an offence specified or involved in any such substituted finding, shall have effect as if it were a finding or sentence of a court martial.