5. — (1) A Justice of the District Court may, if he so thinks proper on the application of the creditor or of the debtor, do in respect of any instalment order (whether made before or after the passing of this Act) whichever of the following things is applicable, that is to say:—

(a) where such instalment order requires the debt and costs to be paid in one payment, vary such order so as to provide (in lieu of such payment in one sum) for payment of the debt and costs by such instalments and at such times as such Justice shall in all the circumstances think reasonable;

(b) where such instalment order requires the debt and costs to be paid by instalments, vary such order in such manner as such Justice may think proper in respect of the number of instalments, the amount of the instalments, or the times at which the instalments are to be paid or all or any two of those matters.

(2) Whenever a Justice of the District Court makes under this section, whether on the application of the creditor or the application of the debtor, an order varying an instalment order, such Justice may, if he so thinks proper, do either or both of the following things, that is to say:—

(a) direct that the costs of the creditor in respect of the application for such variation order shall be part of the costs of the proceedings in the District Court within the meaning of section 17 of the Principal Act;

(b) direct that such variation order shall apply and have effect as from a specified date prior to the date thereof.

(3) Save as provided by the preceding sub-sections of this section, an order under this section shall have effect from the date thereof.

F3[(4) An order under this section varying an instalment order shall not so operate as to make the instalment order enforceable after the expiration of twelve years from the date of the relevant judgment, order or decree.]