(1) Nothing in subsection 66L(3), or in this Subdivision (apart from subsection (2) of this section), affects the recovery of arrears due under a child maintenance order in relation to a child when the order ceases to be in force.
(2) If arrears are due under such an order when the order ceases to be in force, the court may, by order, retrospectively:
(a) discharge the order if there is just cause for doing so; or
(b) vary the order so as to increase or decrease the arrears to be paid under the order if the court is satisfied that:
(i) the circumstances of the person liable to pay the arrears are such as to justify the variation; or
(ii) the circumstances of the person entitled to receive the arrears are such as to justify the variation; or
(iii) in the case of an order that operated in favour of, or that was binding on, a legal personal representative--the circumstances of the estate are such as to justify the variation.