NEC3 ECC Option X7

I am currently involved in an ECC Option C contract where, at one point, a four week delay to the Completion Date looked likely with the possibility of delay damages being applied.

However, the project is finished and the majority of the delay was mitigated with Completion ultimately only one week after the Completion Date.

The Employer is content not to pursue delay damages for one week but what is the best way of formalising this? Is it a case of the Employer and Contractor using 12.3 to alter the Contract Data to remove X7 or adjust the Completion Date?

Whilst it isn’t a requirement of NEC3 many parties still like commercial conclusivity at the end of the contract to wrap up all outstanding matters in a final account settlement agreement that states words to the effect of “full and final settlement of all matters arising under this contract”. This approach takes care of everything, not just liability to pay delay damages.