The citation and a copy of the petition shall be served on the proposed conservatee at least 15 days before the hearing. Service shall be made in the manner provided in Section 415.10 or 415.30 of the Code of Civil Procedure or in such manner as may be authorized by the court. If the proposed conservatee is outside this state, service may also be made in the manner provided in Section 415.40 of the Code of Civil Procedure.