Versions of s. 162(1)(a)

if the parties did not agree that the arbitration should be conducted by a panel of three arbitrators, to the arbitrator, if any, named under paragraph 161(2)(e) or, if that arbitrator is not, in the opinion of the Agency, available to conduct the arbitration or no arbitrator is named, to an arbitrator on the list of arbitrators referred to in section 169 who the Agency chooses and determines is appropriate and available to conduct the arbitration; and