The provisions of this section shall not apply to ordinary policies issued on or after the operative date as defined in § 38.2-3209. In the case of ordinary policies issued on or after the operative date of § 38.2-3215, all adjusted premiums and present values referred to in §§ 38.2-3202 through 38.2-3205 shall be calculated on the basis of the Commissioners 1958 Standard Ordinary Mortality Table and the rate of interest specified in the policy for calculating cash surrender values and paid-up nonforfeiture benefits. However, the rate of interest shall not exceed (i) 3 1/2 percent per year for policies issued before July 1, 1975, (ii) four percent per year for policies issued on or after July 1, 1975, and prior to July 1, 1979, and (iii) 5 1/2 percent per year for policies issued on or after July 1, 1979. Notwithstanding the foregoing provisions of this section, the rate of interest for any single premium whole life or endowment insurance policy issued on or after July 1, 1979, may be a rate not exceeding 6 1/2 percent per year. For any category of ordinary insurance issued on female risks, adjusted premiums and present values may be calculated according to an age not more than six years younger than the actual age of the insured. In calculating the present value of any paid-up term insurance with any accompanying pure endowment offered as a nonforfeiture benefit, the rates of mortality assumed may be not more than those shown in the Commissioners 1958 Extended Term Insurance Table. For insurance issued on a substandard basis the calculation of any adjusted premiums and present values may be based on any other table of mortality specified by the insurer and approved by the Commission.