Section 19048 Of Article 3. Deficiency Assessments From California Revenue And Taxation Code >> Division 2. >> Part 10.2. >> Chapter 4. >> Article 3.

. The board's determination becomes final upon the expiration of 30 days from the time of the determination unless within the 30-day period the taxpayer or the Franchise Tax Board files a petition for rehearing with the board. In that event the determination becomes final upon the expiration of 30 days from the time the board issues its opinion on the petition.