A party or support enforcement agency seeking to modify, or to modify and enforce, a foreign child-support order not under the convention may register that order in this State under Sections 63-17-3610, 63-17-3620, 63-17-3630, 63-17-3640, 63-17-3710, 63-17-3720, 63-17-3730, and 63-17-3740 if the order has not been registered. A petition for modification may be filed at the same time as a request for registration, or at another time. The petition must specify the grounds for modification.