(1) The authority, as of the transfer date, immediately shall assume and be bound by any existing collective bargaining agreements applicable to employees of the local government whose employment is transferred to the authority either as a result of the authority's express assumption of the employees or by application of section 19 for the remainder of the term of the collective bargaining agreement. Local government employees whose employment is not transferred to the authority shall be reassigned within the local government, pursuant to the terms of any applicable collective bargaining agreements. A representative of the employees or a group of employees in the local government who represents or is entitled to represent the employees or a group of employees of the local government pursuant to 1947 PA 336, MCL 423.201 to 423.217, shall continue to represent the employee or group of employees after the employees transfer to the authority. This subsection does not limit the rights of employees, pursuant to applicable law, to assert that a bargaining representative protected by this subsection is no longer their representative. The rights and benefits protected by this subsection may be altered by a future collective bargaining agreement or, for employees not covered by collective bargaining agreements, by benefit plans as established and adopted by the authority.

    (2) Transferred employees shall not by reason of the transfer have their accrued local government pension benefits or credits diminished. If a transferring employee is not vested in his or her local government pension rights at the time of transfer, his or her posttransfer service with the authority shall be credited toward vesting in any local government retirement system in which the transferring employee participated prior to the transfer, but posttransfer service with the authority shall not be credited for any other purpose under the local government's retirement system, except as provided in subsection (4).

    (3) A transferred local government employee described in this section or a person hired by the authority as a new employee after the transfer date may remain or become a participant in the local government retirement system until the authority has established its own retirement system or pension plan. During the period the employee remains or is a participant in the local government system, the employee's posttransfer service with the authority and his or her posttransfer compensation from the authority shall be counted in determining both eligibility for and the amount of pension benefits that the employee will be eligible to receive from the local government system or plan.

    (4) If the local government maintains a retirement system that provides for continuing participation and benefit accrual by local government employees who transfer their employment to another entity in conjunction with transfer of a local government function to that entity, then the transferred employee may elect to remain a participant in the local government retirement system in lieu of participation in any retirement system or pension plan of the authority. If the transferred employee elects to remain a participant in the local government system, the employee's posttransfer service with the authority and his or her posttransfer compensation from the authority shall be counted in determining both eligibility for and the amount of pension benefits that the employee will be eligible to receive from the local government system or plan. Any election to remain in a local government system or plan shall be made within 60 days following the date the authority has established its own retirement system or pension plan and shall be irrevocable. Employees eligible to make the election described in this subsection shall be those employees who immediately before their transfer date were participating in the local government system and who agree to make any employee contributions required for continuing participation in the local government system and also agree to meet all requirements and be subject to all conditions that, from time to time, apply to employees of the local government who participate in the local government system.

    (5) For each employee meeting the requirements of subsection (4) who elects to remain a participant in the local government retirement system, the authority shall, on a timely basis, contribute, as applicable, to the trustees of that retirement system an amount determined by the local government system's actuary to be sufficient to fund the liability for all of that employee's retirement and other postemployment benefits under the system on a current basis, as those liabilities are accrued from and after the transfer date.