Under option A, can the Contractor change the method that the pricing was based upon and shown in the Accepted Programme?
Yes, if the activity schedule no longer reflects the programme then under 54.1 the Contractor can submit a revised activity schedule for acceptance. As long as the costs on that revised activity schedule are in line with the revised programme, add up to the correct number and are sensibly distributed then there should be no reason not to accept that activity schedule which will then become THE activity schedule which they will then be paid against.
Is it a CE for the Contractor to change the piling method?
If it is a CE to reduce the total Defined Cost, so then 63.12 applies?
No - unless the reason for the piling method change was instructed by the Project Manager and was not a constraint in the original Works Information/Scope. The revised activity schedule is just agreeing the redistribution of the same total of Prices to reflect changed method of working.
- not a CE because of ‘exception’ case under 60.1(1) (2nd bullet)?
- It is not a CE. so both 63.12 & 63.14 are not applicable. Am I correct?
Actually - it is not a CE under 60.1(1) full stop as the Activity Schedule is not Works Information!
Either way, yes it is not a CE so you would not read on as far and apply anything further including 63.12/14