The provisions of Article 120, paragraphs (3) through (5) of the new Income Tax Act (including as those provisions are applied mutatis mutandis pursuant to Article 122, paragraph (3), Article 123, paragraph (3), Article 125, paragraph (4), and Article 127, paragraph (4) of the new Income Tax Act) apply in the case where a Tax Return for income tax for tax year 2017 or a subsequent tax year is filed on or after January 1, 2018, and the provisions then in force continue to govern the case where a Tax Return was filed before that date and the case where a Tax Return for income tax for tax year 2016 or an earlier tax year is filed on or after that date.