If the provisions of the Retiree Health Care Act [N.M. Stat. Ann. Chapter 10, Article 7C] do not apply to a retired member, that retired member may continue to be insured under the provisions of any state group insurance plan in effect at the time of retirement or under the terms of any separate subsequent state group insurance plan, if the retired member pays the entire periodic premium charges for such insurance and consents to have the periodic premium charges deducted from the retired member’s pension.