The provisions of Article 65, paragraphs (2) and (3) (Penalty Tax for Understatement) of the new Act on General Rules for National Taxes apply to national tax whose statutory tax return due date as prescribed in Article 2, item (vii) (Definitions) of the new Act on General Rules for National Taxes (including a due date deemed to be that statutory tax return due date under the provisions of the national tax laws, and, for a return of refund claim as prescribed in Article 61, paragraph (1), item (ii) (Special Provisions on the Period Serving as the Basis for Calculating the Amount of Delinquent Tax) of the new Act on General Rules for National Taxes, meaning the day on which that return was filed; hereinafter referred to as the "statutory tax return due date" in this paragraph) arrives on or after the effective date, and with regard to the imposition of penalty tax for understatement on national tax whose statutory tax return due date arrived before the effective date, the provisions then in force continue to govern.