A regional educational service center may be established in any regional state planning area designated in accordance with section 16a-4a upon approval by the State Board of Education of a plan of organization and operation submitted by four or more boards of education for the purpose of cooperative action to furnish programs and services. Except where the pupil population is over fifty thousand in a given planning area, only one regional educational service center may be established in such area. In no case shall there be more than two educational service centers in any such area and in no case shall a board of education be a member of more than one regional educational service center. If, after the establishment of a regional educational service center, boards of education vote to withdraw so that fewer than four such boards are members or the State Board of Education denies continued approval pursuant to section 10-66h, the center shall cease to exist at the end of the subsequent fiscal year.