As his pro rata share of the expense of administration of this Part, each handler shall, on or before the date specified for making payment to the producer settlement fund pursuant to section 20.72 of this Part, pay to the market administrator a sum not exceeding five cents per hundredweight on the total quantity of pool milk received from dairy farmers at plants or from farms in a unit operated by such handler, directly or at the instance of a cooperative association of producers and on the quantity for which payment is made pursuant to section 20.60(d)(2), (3) and (4) of this Part, the exact amount to be determined by the market administrator subject to review by the Secretary. This section shall not be deemed to duplicate any similar payment by any handler under an order issued by the Commissioner of Agriculture and Markets of the State of New York, or the Director of the Division of Dairy Industry of the New Jersey Department of Agriculture, with respect to the marketing area. Whenever verification by the market administrator discloses an error in the payment made by any handler, such error shall be adjusted not later than the date next following such disclosure on which payments are due pursuant to this section.