I. For all child support obligations payable through the department, service of all papers relating to the enforcement of an existing obligation for support including, but not limited to, hearing notices, support violation notices, show cause notices, and motions and notices pursuant to N.H. Rev. Stat. Chapter 161-B shall be deemed legally sufficient service if mailed first class to the last address provided by the obligor to the court pursuant to this chapter, provided that the obligor knew of the obligation to report any change of address. Knowledge is presumed if the court, in accordance with N.H. Rev. Stat. § 161-B:9, notified the obligor of the requirement to report any change of address.
II. A court shall not stay the proceedings or refuse a hearing relating to enforcement of an existing support obligation when service has been made pursuant to this section.