(cf Model Law Art 15)
Where the mandate of an arbitrator terminates under section 13 or 14 or
because of the arbitrator's withdrawal from office for any other reason or
because of the revocation of the arbitrator's mandate by agreement of the
parties or in any other case of termination of the arbitrator's mandate, a
substitute arbitrator must be appointed according to the rules that were
applicable to the appointment of the arbitrator being replaced.