a. If the PM has accepted the quotation of £27K, the CE has been implemented, so the Contractor is paid £27K - Clause 65.2 is the relevant clause.
b. The situation is the same under all main options A to E - the assessment of the CE is based on change in defined cost and is not changed if the forecast turns out to have been incorrect.
c. Under Clause 63.1, the fact that the CE has not been 'agreed' is irrelevant - the assessment is based on actual Defined Cost of work carried out before the 'dividing date' and the forecast Defined Cost of work to be carried out after that date. In this case the dividing date is the date of the PM's instruction to change the WI - this is the same across all main options.
d. No.
e. Not sure what you mean here.
Note that if you don't like the answer to the first part of the question, ask yourself how you would have felt if the CE had been implemented at a value of £20K and the actual cost had turned out to be £27K.
b. The situation is the same under all main options A to E - the assessment of the CE is based on change in defined cost and is not changed if the forecast turns out to have been incorrect.
c. Under Clause 63.1, the fact that the CE has not been 'agreed' is irrelevant - the assessment is based on actual Defined Cost of work carried out before the 'dividing date' and the forecast Defined Cost of work to be carried out after that date. In this case the dividing date is the date of the PM's instruction to change the WI - this is the same across all main options.
d. No.
e. Not sure what you mean here.
Note that if you don't like the answer to the first part of the question, ask yourself how you would have felt if the CE had been implemented at a value of £20K and the actual cost had turned out to be £27K.