The provisions of section 589(4) to (6) of, and paragraph 11 of Schedule 7 to, the Housing Act 1985 (which relate to apportionment by reference to gross rateable values) apply only for rate periods, within the meaning of the M1General Rate Act 1967, beginning on or after the first date after 1st April 1986 on which new valuation lists come into force under section 68(1) of that Act.