(1) If, before the date set for hearing, application is made to the court for leave to present additional evidence and it is shown to the satisfaction of the court that the additional evidence is material, relates to the validity of the agency action, and that: there were good reasons for failure to present it in the proceeding before the agency, the court may remand the matter to the agency with directions that the agency receive additional evidence and conduct additional factfinding.
(2) there were alleged irregularities in procedure before the agency, the court may take proof on the matter.
(3) The agency may modify its action by reason of the additional evidence and shall file any modifications, new findings, or decisions with the reviewing court.