27 Filling of vacancy, &c.E+W+N.I.
(1)Where an arbitrator ceases to hold office, the parties are free to agree—
(a)whether and if so how the vacancy is to be filled,
(b)whether and if so to what extent the previous proceedings should stand, and
(c)what effect (if any) his ceasing to hold office has on any appointment made by him (alone or jointly).
(2)If or to the extent that there is no such agreement, the following provisions apply.
(3)The provisions of sections 16 (procedure for appointment of arbitrators) and 18 (failure of appointment procedure) apply in relation to the filling of the vacancy as in relation to an original appointment.
(4)The tribunal (when reconstituted) shall determine whether and if so to what extent the previous proceedings should stand.
This does not affect any right of a party to challenge those proceedings on any ground which had arisen before the arbitrator ceased to hold office.
(5)His ceasing to hold office does not affect any appointment by him (alone or jointly) of another arbitrator, in particular any appointment of a chairman or umpire.