The Justices of the Supreme Court and the Judges of the Superior Court shall hold their offices for initial terms of 7 years and upon reappointment shall hold their offices during good behavior; provided however, that, upon the abolition of the juvenile and domestic relations courts or family court and county district courts as provided by law, the judges in office in those former courts who have acquired tenure and the Judges of the Superior Court who have acquired tenure as a judge in those former courts prior to appointment to the Superior Court, shall have tenure as Judges of the Superior Court. Judges of the juvenile and domestic relations courts or family court and county district courts who have not acquired tenure as a judge of those former courts shall hold their offices for the period of their respective terms which remain unexpired and shall acquire tenure upon reappointment to the Superior Court. Such justices and judges shall be retired upon attaining the age of 70 years. Provisions for the pensioning of the Justices of the Supreme Court and the Judges of the Superior Court shall be made by law.