It is true that unless agreed, The Amended Act shall not apply to Arbitral Proceedings, commenced before the The Amendment Act, in accordance with The Principal Act.
“In Union of India v. M.P. Gupta (2004) 10 SCC 504; Union of India v. V.S. Engineering (P) Ltd., (2006) 13 SCC 240; Union of India v. Singh Builders Syndicate (2009) 4 SCC 523 the Court held that whenever the agreement specifically provides for appointment of Named Arbitrators, the appointment of Arbitrator should be in terms of the contract.
In the case of public institutions which are slow in responding to the request for appointment of an Arbitrator, the power of the High Court to appoint an Arbitrator under Section 11 is not taken away. It will then be in the discretion of the Chief Justice/Designated Judge to appoint as per the contract or a High Court Judge. When the agreement specifically provides for appointment of Named Arbitrators, the appointment should be in terms of the agreement.”
– Hon’ble Justice R. Banumathi, Union of India v. Pradeep Vinod Construction Company, [Civil Appeal No. 6400 of 2016].