NEC ECS: Clarification of what sub-contract working to (NEC3 Option A)

If a Contractor has issued a Subcontract to their supply chain, and the supply chain have struck through a number of elements and signed/ returned this to the contractor - but the Contractor has not responded - which contract is legally binding? The issued contract [by the Contractor] or the amended and signed [by Subcontractor only] that was not responded to by the Contractor?

Worth noting works mostly complete and measured works paid.

Firstly, if you stand to lose a lot of money based on this it would be worthwhile taking advice as the answer will depend on the exact wording contained in pre-contract correspondence. As such it’s difficult to give a view based on the limited information you’ve provided.

In a general sense, the act of amending and returning the subcontract could be seen to be a counter-offer, unless you had already commenced work before it was returned, in which case your actions could be seen as acceptance of the terms proposed by the contractor. If you hadn’t commenced work before returning the amended terms then the act of payment or absence of a further counter-offer by the contractor could be seen as acceptance of your counter-offer.