(a) Any authority competent to convene, for the command in which the accused is serving or assigned, a court of the kind that imposed the sentence may remit or suspend any part or amount of the unexecuted part of any sentence, including all uncollected forfeitures other than a sentence approved by the Governor.
(b) The Governor may, for good cause, substitute an administrative form of discharge for a discharge or dismissal executed in accordance with the sentence of a court–martial.