Assuming completion of the whole of the works has been achieved, the instruction will have no effect upon the defects date. This is because the defects date is defined as being ‘xx’ weeks after completion of the whole of the works in the contract data part one. Of course ‘xx’ is the number of weeks inserted in the contract data in your particular contract. Completion is not affected as it has already been certified. The value of the compensation event will have to reflect the additional defined costs to the contractor of carrying out and managing isolated works after its resources have left site.