(a) Rulings of the presiding officer may not be appealed prior to or during the course of the hearing, or subsequent thereto, if the proceeding is still before him or her, except where the presiding officer finds it necessary to allow an appeal to the Commission to prevent substantial delay, expense, or detriment to the public interest, or undue prejudice to a party.

(b) Any party seeking to appeal must file a motion for leave to appeal no later than fifteen (15) days after written service or oral notice of the ruling in question, unless the presiding officer, for good cause shown, enlarges or shortens the time. Any such motion must contain the grounds for leave to appeal and the appeal itself.

(c) Replies to the motion for leave to appeal and the appeal may be filed within fifteen (15) days after date of service thereof, unless the presiding officer, for good cause shown, enlarges or shortens the time. If the motion is granted, the presiding officer must certify the appeal to the Commission.

(d) Unless otherwise provided, the certification of the appeal will not operate as a stay of the proceeding before the presiding officer.

(e) The provisions of § 502.10 do not apply to this section. [Rule 221.]