We are the MWC and have a Subcontractor under an NEC3 Option A Subcontract.
The Subcontractor asked if we could pay 2 payment certificates at the same time for which they would give us a discount to the Subcontract price.
This has now been agreed and processed but how would we reduce the prices as it’s not a Compensation Event etc.?
You have inadvertently modified the contract. To make this legal, you both need to sign - as in directors who would normally sign contracts in order to enter into them - a supplementary agreement confirming this agreement.
Jon is right - but given this is likely to be for a very small amount then you would like to think you can both find a way just by mutual agreement. You could by agreement make it fit a negative CE, or under NEC4 you could use a Contractors proposal equivalent to value engineering.