Additional Pay for Additional Work. The salary of a member of the Unit shall be the limit of remuneration for the appointment or duty year. When an administrator is required to perform duties above and beyond those reasonably expected under his/her position duties statement, he/she may receive additional remuneration at his/her regular rate, or at some other lower rate, when recommended for such additional remuneration by proper authority and with approval, in advance, by the Superintendent of Schools.