Moneys collected by any commodity commission pursuant to any marketing order from any assessment for marketing purposes or as an advance deposit thereon shall be used by the commission only for the purpose of paying for the costs or expenses arising in connection with carrying out the purposes and provisions of such agreement or order.

Upon the termination of any marketing order any and all moneys remaining with the commodity commission operating under that marketing order and not required to defray expenses or repay obligations incurred by that commission shall be returned to the affected producers in proportion to the assessments paid by each in the two year period preceding the date of the termination order.