Section 227.49 - Petitions for rehearing in contested cases(1) A petition for rehearing shall not be a prerequisite for appeal or review. Any person aggrieved by a final order may, within 20 days after service of the order, file a written petition for rehearing which shall specify in detail the grounds for the relief sought and supporting authorities. An agency may order a rehearing on its own motion within 20 days after service of a final order. This subsection does not apply to s. 17.025(3) (e). No agency is required to conduct more than one rehearing based on a petition for rehearing filed under this subsection in any contested case.(2) The filing of a petition for rehearing shall not suspend or delay the effective date of the order, and the order shall take effect on the date fixed by the agency and shall continue in effect unless the petition is granted or until the order is superseded, modified, or set aside as provided by law.(3) Rehearing will be granted only on the basis of: (a) Some material error of law.(b) Some material error of fact.(c) The discovery of new evidence sufficiently strong to reverse or modify the order, and which could not have been previously discovered by due diligence.(4) Copies of petitions for rehearing shall be served on all parties of record. Parties may file replies to the petition.(5) The agency may order a rehearing or enter an order with reference to the petition without a hearing, and shall dispose of the petition within 30 days after it is filed. If the agency does not enter an order disposing of the petition within the 30-day period, the petition shall be deemed to have been denied as of the expiration of the 30-day period.(6) Upon granting a rehearing, the agency shall set the matter for further proceedings as soon as practicable. Proceedings upon rehearing shall conform as nearly may be to the proceedings in an original hearing except as the agency may otherwise direct. If in the agency's judgment, after such rehearing it appears that the original decision, order or determination is in any respect unlawful or unreasonable, the agency may reverse, change, modify or suspend the same accordingly. Any decision, order or determination made after such rehearing reversing, changing, modifying or suspending the original determination shall have the same force and effect as an original decision, order or determination.1975 c. 94 s. 3; 1975 c. 414; 1977 c. 139; 1979 c. 208; 1985 a. 182 s. 33t; Stats. 1985 s. 227.49. This section does not require service of a petition for rehearing within 20 days of service of the order, only filing. DOR v. Hogan, 198 Wis. 2d 792, 542 N.W.2d 148 (Ct. App. 1995), 95-0438. Filing of a petition for rehearing under sub. (1) is not accomplished upon its mailing. A petition is filed when it is physically delivered to and received by the relevant authority. Currier v. Wisconsin Department of Revenue, 2006 WI App 12, 288 Wis. 2d 693, 709 N.W.2d 520, 05-0292. In this case, where the analysis set forth in an order of the Public Service Commission (PSC) denying a petition for rehearing under this section was analogous to the PSC's decision in the underlying matter, the decision denying the rehearing met the definition of an administrative decision for purposes of being subject to judicial review under s. 227.52. The substantial evidence standard under s. 227.57(6) therefore applied with respect to review of the PSC's findings of fact underlying the PSC's decision on whether to grant rehearing. Town of Holland v. Public Service Commission, 2018 WI App 38, 382 Wis. 2d 799, 913 N.W.2d 914, 17-1129.