IRS (Federal) 가 먼저 연장, 이후 State 이 연장했습니다.
https://www.irs.gov/newsroom/irs-may-15-tax-deadline-extended-to-oct-16-for-disaster-area-taxpayers-in-california-alabama-and-georgia

저도 아리까리해서 회사 회계사에게 물어보니 CA 경우, 피해자들을 거주민 모두를 해당자로 지정했습니다.
Federal & CA State 모두 합의

The IRS is offering the extension to people in areas designated by the Federal Emergency Management Agency (FEMA). Included areas cover the most populous parts of the state, including Los Angeles, San Diego, Orange, Riverside, Sacramento and San Francisco counties.

Due to recent winter storms in California, the IRS and Governor Gavin Newsom’s office say the new deadline to file and pay your taxes is now October 16th for San Diego County and just about all of California; something that several tax professionals say rarely happens.

https://www.cbs8.com/article/news/local/working-for-you/tax-deadline-for-all-san-diegans-october-16th/509-cbefb862-efc9-4cee-aa56-6951d1996992

https://www.cbsnews.com/essentials/irs-announcement-the-2023-tax-deadline-just-changed-for-most-california-residents-are-you-one-of-them-2023-03-14/#:~:text=What%20is%20the%20new%20tax,returns%20and%20make%20tax%20payments.

https://www.irs.gov/forms-pubs/extension-of-time-to-file-your-tax-return