Every term of imprisonment imposed on an offender in default of payment of a fine or sum of money must, unless otherwise directed by the court, be served:
(a) cumulatively on any incomplete sentence or sentences of imprisonment imposed on the offender for the default of a payment of a fine or sum of money; and
(b) concurrently with any incomplete sentence or sentences of imprisonment imposed on the offender, whether the other sentence was or the other sentences were imposed before or at the same time as that term.