A party or support enforcement agency seeking to modify, or to modify and enforce, a child support order issued in another state shall register that order in this state in the same manner provided in §§ 36-5-2601 - 36-5-2608 if the order has not been registered. A petition for modification may be filed at the same time as a request for registration, or later. The pleading must specify the grounds for modification.
T.C.A. § 36-5-2609