Nothing contained in § 24-12-129 should be interpreted to prevent a municipality from providing benefits contained in § 24-12-129 to retirees who are less than age fifty-five (55) or who have completed fewer than twenty (20) years of municipal service. Further, any person who qualified and participated in a municipal health care plan under § 24-12-129 shall continue to be eligible to participate in the health care plan after August 1, 1997.