For the purpose of determining whether the initial order shall be continued, not later than 22 months after the issuance of the order (or any earlier date recommended by the Board), the Secretary shall conduct a referendum among persons who have been producers or importers during a representative period, as determined by the Secretary. The order shall be continued only if the Secretary determines that it has been approved by not less than a majority of the producers voting in the referendum who, during a representative period as determined by the Secretary, have been engaged in the production of cattle. If continuation of the order is not approved by a majority of those voting in the referendum, the Secretary shall terminate collection of assessments under the order within six months after the Secretary determines that continuation of the order is not favored by a majority voting in the referendum and shall terminate the order in an orderly manner as soon as practicable after such determination.