A contracting agency that is not an employer or that ceases to be an employer for purposes of this chapter shall thereafter make contributions as otherwise provided in Chapter 5 (commencing with Section 20460). Except as provided in Section 20578, if a contracting agency ceases to be an employer for purposes of this section, its contributions thereafter and the accumulated contributions credited to or held as having been made by the agency adjusted by addition of all contributions thereafter made by the employer and subtraction of amounts paid thereafter to or on account of employees of the contracting agency shall be held, on and after the date upon which the contracting agency ceases to be an employer, exclusively for the benefit of its employees, retired employees and beneficiaries of the employees and retired employees.
A contracting agency shall not be an employer for purposes of this section, if the board determines that the agency has no active employees eligible for coverage under this section.