Terminal float query

We are Working under nec4 option A.

The client has requested that we work weekends to meet a intermediate within the programem. This is not not a key date within the contract just a request to help with the clients follow on works and recovered under dayworks. No risk on ourselves to not meet this date.

Ultimately working weekends will bring our planned completion date forward of the contract completion.

In this instance would this give entitlement of terminal float as it could be construed as change in scope works?

Yes, it would increase the terminal float (that the Contractor owns). The only way the completion date could be shorten under this scenario is if the PM was asking you for a quote for acceleration which does not appear to be the case