19d. Unless a written Order of the Board bears upon its facts the consent, approval as to form, or acknowledgment of receipt of a copy thereof, signed by each interested party or his authorized representative, notice of the Board's Order shall be given by mailing postage prepaid and addressed to the addresses of record in the case, or hand delivering, a copy thereof to each such party or representative not less than three nor more than five days prior to the effective date of the Order.
19e. The Board may require presentation of a proposed Order or Orders disposing of any case or matter.
19f. So long as the Board finds it to be administratively practicable, the Board shall endeavor to render a decision or determination or opinion with respect to any case or matter within 120 days of the matter being submitted to the Board. For purposes of this rule a matter is not deemed to be submitted to the Board until all briefing or supplemental briefing and the hearing described in Rule 16 (if any) has been completed. Failure of the Board to render such decision or determination or opinion within such prescribed time shall not alter or affect the rights of any party before the Board.
19g. Nothing in the foregoing paragraphs shall be construed to limit or otherwise affect the application of Rule XX (concerning computation of amount).
20. Where the Board has promulgated or entered its opinion determining the issues in proceeding, it may withhold entry of a final Order for the purpose of permitting the parties to submit computations pursuant to the Board's determination of the issues showing the correct amount of the deficiency, abatement, overpayment or other sum to be entered as the decision. If the parties are in agreement as to the amount to be entered in the decision of the Board, then all of them shall file promptly with the Board a computation showing the amount of deficiency, abatement, overpayment or sum and that there is no disagreement that the figures shown are in accordance with the decision of the Board. The Board will then enter its final order. If however, the parties are not in agreement as to the amount of the figures to be entered as the decision in accordance with the opinion of the Board either of them may, after service as provided in Rule IX upon all interested parties, file with the Board a computation of the deficiency, abatement, overpayment or other sum believed by him to be in accordance with the opinion of the court. The secretary of the Board will place the matter upon the calendar of the Board for argument and will notify the parties in interest. If no opposing party files an objection accompanied by an alternative computation at least five days prior to the time of such argument or continuance thereof, the Board may enter its final Order in accordance with the computation already submitted.
Any argument under this rule will be confined solely to the consideration of the correct computation resulting from the opinion already rendered. No argument will be heard upon or consideration given to the issues or matters already disposed of. This rule is not to be regarded as a substitute for a motion for rehearing, reargument or reconsideration.