Section 220 ILCS 5/10-113 - Rescission or hearing of order(a) Anything in this Act to the contrary notwithstanding, the Commission may at any time, upon notice to the public utility affected, and after opportunity to be heard as provided in the case of complaints, rescind, alter or amend any rule, regulation, order or decision made by it. Any order rescinding, altering or amending a prior rule, regulation, order or decision shall, when served upon the public utility affected, have the same effect as is herein provided for original rules, regulations, orders or decisions. Within 30 days after the service of any rule or regulation, order or decision of the Commission any party to the action or proceeding may apply for a rehearing in respect to any matter determined in said action or proceeding and specified in the application for rehearing. The Commission shall receive and consider such application and shall grant or deny such application in whole or in part within 20 days from the date of the receipt thereof by the Commission. In case the application for rehearing is granted in whole or in part the Commission shall proceed as promptly as possible to consider such rehearing as allowed. No appeal shall be allowed from any rule, regulation, order or decision of the Commission unless and until an application for a rehearing thereof shall first have been filed with and finally disposed of by the Commission: provided, however, that in case the Commission shall fail to grant or deny an application for a rehearing in whole or in part within 20 days from the date of the receipt thereof, or shall fail to enter a final order upon rehearing within 150 days after such rehearing is granted, the application for rehearing shall be deemed to have been denied and finally disposed of, and an order to that effect shall be deemed to have been served, for the purpose of an appeal from the rule, regulation, order or decision covered by such application. No person or corporation in any appeal shall urge or rely upon any grounds not set forth in such application for a rehearing before the Commission. An application for rehearing shall not excuse any corporation or person from complying with and obeying any rule, regulation, order or decision or any requirement of any rule, regulation, order or decision of the Commission theretofore made, or operate in any manner to stay or postpone the enforcement thereof, except in such cases and upon such terms as the Commission may by order direct. If, after such rehearing and consideration of all the facts, including those arising since the making of the rule, regulation, order or decision, the Commission shall be of the opinion that the original rule, regulation, order or decision or any part thereof is in any respect unjust or unwarranted, or should be changed, the Commission may rescind, alter or amend the same. A rule, regulation, order or decision made after such rehearing, rescinding, altering or amending the original rule, regulation, order or decision shall have the same force and effect as an original rule, regulation, order or decision, but shall not affect any right or the enforcement of any right arising from or by virtue of the original rule, regulation, order or decision unless so ordered by the Commission. Only one rehearing shall be granted by the Commission; but this shall not be construed to prevent any party from filing a petition setting up a new and different state of facts after 2 years, and invoking the action of the Commission thereon.(b) Notwithstanding any contrary or inconsistent provision in the Illinois Administrative Procedure Act, the Commission may, in accordance with this Section, make a change in a rule or regulation adopted or modified pursuant to Section 5-40 of the Illinois Administrative Procedure Act, upon consideration of an application for rehearing of the Commission's order directing that the rule or regulation be filed with the Secretary of State and published in the Illinois Register pursuant to subsection (d) of Section 5-40. The Commission shall provide the parties to the original hearing in which the rule was adopted or modified no less than 7 days notice to provide responses to the change the Commission proposes to make. Any such change shall be based upon evidence submitted in the record in the original hearing or in the rehearing. If the Commission makes such a substantive change in the rule or regulation pursuant to this subsection, it shall provide notice of the amendment to the rule or regulation to the Joint Committee on Administrative Rules in accordance with subsection (c) of Section 5-40, and shall thereafter comply with the requirements of subsection (d) of Section 5-40 with respect to the rule or regulation as amended. The running of the time period specified in subsection (e) of Section 5-40 of the Illinois Administrative Procedure Act for completing a rulemaking proceeding shall be tolled for the period of time necessary for the Commission to receive and consider an application for rehearing and to conduct any proceedings on rehearing, provided, that such tolling shall not serve to extend any of the time periods provided for in subsection (a) of this Section. P.A. 90-561, eff. 12/16/1997.