For good cause, the commissioner may extend the time within which a business enterprise is required to file a return, and if such return is filed during the period of extension no penalty may be imposed for failure to file the return at the time required by this chapter, but the enterprise shall be liable for interest and late payment charges as prescribed in N.H. Rev. Stat. § 21-J:28 and N.H. Rev. Stat. § 21-J:33. Failure to file the return during the period of the extension shall void the extension.