There is hereby created a one-time early retirement for any member of the Mississippi Highway Safety Patrol Retirement System who has at least twenty (20) years' of service. A superannuation retirement taken under the provisions of this section shall not be subject to the three percent (3%) penalty for a member who is below the age of fifty-five (55) years as provided in Section 25-13-11(d), Mississippi Code of 1972. A retirement under the provisions of this section shall be based upon the current fiscal year's salary of the applicant. No member of the Mississippi Highway Safety Patrol Retirement System may avail himself of the benefits provided in this section from and after June 30, 1986.