Each local government which provides an employer-sponsored group health care benefits plan for the employees of the local government shall make coverage under such group health care benefits program available to retired former employees and their dependents, upon written application filed with the clerk or secretary thereof within 30 days following retirement of the employee, as provided by this section. Coverage under the employee group health care benefits plan may cease to be made available upon (1) the retired employee attaining age 65, (2) the retired employee failing to make required premium payments on a timely basis, or (3) the retired employee becoming covered or becoming eligible to be covered under a plan of another employer.