A proceeding shall stand submitted for decision by the commission after the ..ling of the petition and holding of the settlement conference, the ..ling of such briefs or the presentation of such oral argument as may have been prescribed by the commission or the presiding officer, and the submission of all exhibits. The commission's formal opinions and orders shall be issued and filed as soon as practicable after proceedings have been submitted.
Mo. Sup. Ct. Op. R 12-21.03