If the aggregate amount of assessment surcharges received by an Association member during a surcharge year is less than that Association member’s assessment payment, the Association member’s assessment surcharge authorized under § 20–406 of this subtitle shall be increased accordingly for the next appropriate surcharge year. If the aggregate amount of assessment surcharges received by an Association member during a recoupment year exceeds the Association member’s assessment payment, the Association shall promptly return the excess to the association member. An Association member to whom an excess is returned under paragraph (1) of this subsection shall: refund the excess to the policyholders who paid the excess; or apply the excess as an expense reduction in a subsequent rate filing.