As per case facts, legal heirs challenged a development agreement due to alleged fraud by a developer and an executor, and contested a Will. An arbitrator was already appointed to ... resolve disputes between the developer and executor. The legal heirs sought to intervene in the ongoing arbitration and also filed two applications: one for the appointment of a new arbitrator, and another for the termination of the existing arbitrator's mandate due to delays and alleged failure to act without undue delay. The Supreme Court had previously granted the legal heirs liberty to approach the *already appointed* arbitrator to ventilate their grievances, directing the arbitrator to consider their claims and cross-claims, thereby widening the scope of the existing reference. The question arose whether a new arbitrator should be appointed or the existing arbitrator's mandate terminated, given the Supreme Court's directive and prior applications filed in other courts. Finally, the Court dismissed the application for a new arbitrator, citing the Supreme Court's widened scope for the existing arbitration, and dismissed the application for termination of mandate, ruling it was not maintainable before this court under Section 42 of the Act, as a prior application had established jurisdiction in the Commercial Court at Rajarhat for all subsequent matters.