(A) Retirement System. Within two years after the effective date of this constitution, the legislature shall provide for a retirement system for judges which shall apply to a judge taking office after the effective date of the law enacting the system and in which a judge in office at that time may elect to become a member, with credit for all prior years of judicial service and without contribution therefor. The retirement benefits and judicial service rights of a judge in office or retired on the effective date of this constitution shall not be diminished, nor shall the benefits to which a surviving spouse is entitled be reduced.

(B) Mandatory Retirement. Except as otherwise provided in this Section, a judge shall not remain in office beyond his seventieth birthday seventy-fifth birthday. A judge who attains seventy-five years of age. A judge who attains seventy years of age while serving a term of office shall be allowed to complete that term of office.