The provisions of Article 201 (Tax Withheld from Retirement Income) of the new Act as read by replacing terms pursuant to Article 3, paragraph (2) of the Supplementary Provisions, and Appended Table VI of the Supplementary Provisions and the attached table to Appended Table VIII of the new Act, apply to severance pay or other such compensation prescribed in Article 199 (Obligation to Withhold Taxes from Retirement Income) of the new Act (hereinafter referred to as "severance pay or other such compensation") which is payable during 1974 and is paid on or after the effective date, and the provisions then in force continue to govern severance pay or other such compensation payable during that year which was paid before that date.