Waiver of interest and penalty: department urged to withdraw appeals limited to interest or penalty when tax paid. Where the taxpayer has fully paid the tax under demands made under Section 73 and only interest and/or penalty remain in dispute, and the taxpayer otherwise satisfies the conditions of Section 128A and rules, the proper officer may withdraw departmental appeals or accept review-stage orders when the department's appeal concerns only interest calculation or imposition/non-imposition of penalty.