Exhibit 99.1

IN THE UNITED STATES BANKRUPTCY COURT

FOR THE SOUTHERN DISTRICT OF TEXAS

HOUSTON DIVISION

NOTICE OF EFFECTIVE DATE OF THE JOINT PREPACKAGED

PLAN OF REORGANIZATION FOR LONESTAR RESOURCES US INC. AND

ITS AFFILIATE DEBTORS UNDER CHAPTER 11 OF THE BANKRUPTCY CODE

TO ALL CREDITORS, EQUITY INTEREST HOLDERS, AND OTHER PARTIES-IN-INTEREST:

PLEASE TAKE NOTICE that on November 12, 2020, the United States Bankruptcy Court for the Southern District of Texas (the “Bankruptcy Court”) entered the Findings of Fact, Conclusions of Law and Order Approving Debtors’ Disclosure Statement and Confirming the Joint Prepackaged Plan of Reorganization for Lonestar Resources US Inc. and Its Affiliate Debtors Under Chapter 11 of the Bankruptcy Code (the “Confirmation Order”) [Docket No. 219]. Among other things, the Confirmation Order confirmed the Joint Prepackaged Plan of Reorganization for Lonestar Resources US, Inc. and its Debtor Affiliates Under Chapter 11 of the Bankruptcy Code, dated September 28, 2020 (as amended, modified, or supplemented from time to time, the “Plan”)² as satisfying the requirements of the Bankruptcy Code, thereby authorizing Lonestar Resources US Inc. and its debtor affiliates (collectively, the “Debtors”) to implement the Plan on the Effective Date.

PLEASE TAKE FURTHER NOTICE that the Plan was substantially consummated, and the Effective Date (as defined in the Plan) occurred, on November 30, 2020.

PLEASE TAKE FURTHER NOTICE that any party in interest who wishes to continue to receive service of court filings must file a request for such notice with the Bankruptcy Court under Bankruptcy Rule 2002. Parties who previously filed such notices must file new notices if they wish to continue to receive service of court filings.

Counsel for the Debtors and Debtors-in-Possession

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