Termination of a county's participation in a community mental health services program, whether that participation is singular or joint, may be accomplished by an official notification from the county's board of commissioners to the department and the other concerned county boards of commissioners or, in a charter county, by an official notification from the county's board of commissioners upon a request from the county executive. The date of termination shall be 1 year following the receipt of notification by the department, unless the director of the department consents to an earlier termination. In the interim between notification and official termination, the county's participation in the community mental health services program shall be maintained in good faith.