Notwithstanding paragraph (1), if the Director of the Division of Enforcement of the Commission or the Director’s designee determines that a particular enforcement investigation is sufficiently complex such that a determination regarding the filing of an action against a person cannot be completed within the deadline specified in paragraph (1), the Director of the Division of Enforcement of the Commission or the Director’s designee may, after providing notice to the Chairman of the Commission, extend such deadline as needed for one additional 180-day period. If after the additional 180-day period the Director of the Division of Enforcement of the Commission or the Director’s designee determines that a particular enforcement investigation is sufficiently complex such that a determination regarding the filing of an action against a person cannot be completed within the additional 180-day period, the Director of the Division of Enforcement of the Commission or the Director’s designee may, after providing notice to and receiving approval of the Commission, extend such deadline as needed for one or more additional successive 180-day periods.