Cal. INS § 4097.10

At any time before that plan of conversion becomes effective as provided in Section 4097.11, the mutual company may, by resolution of at least two-thirds of the board of directors, amend the plan of conversion or withdraw the plan of conversion. Any plan amendment shall require the written consent of the commissioner. For a plan amendment, all references in this article to the plan of conversion shall be deemed to refer to the plan as amended, but no amendment shall be deemed to change the adoption date of the plan of conversion. No amendment may change the plan of conversion in a manner that the commissioner determines is materially disadvantageous to policyholders of the mutual insurer or members of the mutual holding company, unless a further public hearing is held on the plan as amended, if the amendment is made after the initial public hearing, or if the plan as amended is submitted for reconsideration by the members if the amendment is made after the plan has been approved by the members.