Unless the agreement provides otherwise, the arbitrators shall designate a time and place for hearing and notify the parties, personally or by certified mail, return receipt requested, bearing a postmark from the United States Postal Service, not less than five days before the hearing. Appearance at the hearing waives the notice. Except as provided in § 3-215(b) of this subtitle, the arbitration hearing shall be conducted by all the arbitrators. The arbitrators may adjourn the hearing from time to time as necessary. Upon request of a party and for good cause shown or on their own motion, the arbitrators may postpone the hearing to a time not later than the date set by the agreement for the award, unless the parties consent to a later date. The arbitrators may hear and determine the controversy upon the evidence produced notwithstanding the failure of a party duly notified to appear. On petition of a party, the court may direct the arbitrators to proceed promptly with the hearing and determination of the controversy.