There are no such things as CVI's under the contract and these pieces of paper are pretty meaningless. The only way that the Subcontractor can claim extra cost is if they can notify an event as a compensation event - and only if it is a valid reason under 60.1.
They should be doing the works as stated in the Works Information - and should only be deviating from that if they have a written instruction from the Contractor. Equally the Contractor should not be giving verbal instructions and expecting the Subcontractor to act on them.
Both Parties should have addressed this a lot earlier and stopped it happening. If any of these events are now considered to be valid compensation events then you will have to try to assess them accordingly looking back at the impact that they would have occurred. This should be when either the instruction was given or the compensation event was notified in terms of actual cost before that point and forecast cost beyond that point.
They should be doing the works as stated in the Works Information - and should only be deviating from that if they have a written instruction from the Contractor. Equally the Contractor should not be giving verbal instructions and expecting the Subcontractor to act on them.
Both Parties should have addressed this a lot earlier and stopped it happening. If any of these events are now considered to be valid compensation events then you will have to try to assess them accordingly looking back at the impact that they would have occurred. This should be when either the instruction was given or the compensation event was notified in terms of actual cost before that point and forecast cost beyond that point.