The assessed tax shall be paid no later than April 15th of each year, unless another due date is specified by the Tax Commission. Any taxes assessed shall be paid by check or money order made payable to the Osage Nation Tax Commission. Payment is timely made if it is postmarked before midnight on the date on which the tax is due or if it is delivered to the Tax Commission by certified mail or in person and a receipt is given before midnight on the due date. ONCA 06-10, eff. Sept. 29, 2006.