California Code, Probate Code - PROB § 2593

(a) The court, on its own motion or on petition of any interested person, when it appears to be for the best interests of the ward or conservatee or the estate, may withdraw any or all of the powers previously granted pursuant to this article or may impose restrictions, conditions, and limitations on the exercise of such powers by the guardian or conservator.

(b) Notice of the hearing on a petition under this section shall be given for the period and in the manner provided in Chapter 3 (commencing with Section 1460) of Part 1.