(1) This Part applies to an arbitration commenced after the commencement of this Act under an agreement made before such commencement but does not apply to an arbitration commenced before the commencement of this Act.
(2) For the purposes of this Part an arbitration shall be deemed to be commenced when one party to the arbitration agreement serves on the other party or parties a notice requiring him or them to appoint or concur in appointing an arbitrator, or, when the arbitration agreement provides that the reference shall be to a person named or designated in the agreement, requiring him or them to submit the dispute to the person so named or designated.