Notwithstanding the provisions of the preceding paragraph, the provisions then in force continue to govern, among interest and similar income prescribed in the preceding paragraph (excluding that relating to ordinary deposits and similar deposits; hereinafter referred to as "interest and similar income" in this paragraph) which is to be paid on or after April 1, 1988 and which corresponds to a calculation period for interest and similar income that includes that date, the part of the interest and similar income equivalent to the amount calculated pursuant to Cabinet Order as the amount corresponding to the period from the first day of that calculation period to March 31, 1988.