Cal. Prob. Code § 17201.1

A petitioner in a proceeding under Section 17200 may commence discovery upon a trustee in accordance with the same time periods set forth in the Civil Discovery Act (Title 4 (commencing with Section 2016.010) of Part 4 of the Code of Civil Procedure) except that the time periods shall commence to run upon service of the petition and notice of hearing upon the trustee or the trustee’s appearance in the proceeding, whichever first occurs. Nothing in this section shall alter when a respondent in such a proceeding may commence discovery.