NEC ECC: Does Cl 65.2 have a limit?

[Clause 65.2] When does the quantum of the difference between the forecast and the actual become disproportionate and ‘unfair’ to either party? Is there relief elsewhere in the contract for dealing with this?

No - once implemented that is it. If it costs a lot more, Contractor could try to claim that was due to other reasons that could be a compensation event but the PM would have to agree that it is indeed a new compensation event and request a quote.

The only remedy at that point would be by mutual agreement - but not sure why the Party that has benefited would ever agree to something different if they don’t have to.

Thanks. You final point is, of course, true for the Party benefitting. I was more concerned for the Party suffering.