What does NEC4 clause 60.1(4) mean?

A Key Date is a milestone date in the contract. In the NEC4 main contract the instruction comes from the Project Manager or the Supervisor. On an NEC subcontract it comes from your main contractor. The clause does not ask why the stop was ordered. A stop for your main contractor's convenience, or to allow a survey, counts on its face. The check on stops you caused comes at clause 61.4: there is no change if the event came from your own fault. To rely on the clause, show the instruction and who gave it. Then show what work it stopped or held back, or which Key Date it moved, and when work could restart. Because the event comes from an instruction, your main contractor should notify it when it gives the instruction. If it does not, you notify under clause 61.3, and the 8-week bar does not apply. The change to the Prices, your contract price, is assessed under clause 63.1. It is the effect of the stop on actual Defined Cost for work done by the date of the instruction. Add forecast Defined Cost for work still to do, plus the Fee. For a stop, that normally means standing people and equipment, demobilising and remobilising, and protecting part-finished work. For a Key Date brought forward, it means the extra resources to go faster. Two things go wrong most. A verbal stop on site is never confirmed in writing, so its start date is disputed. Or you keep a full gang standing when the instruction plainly let people be moved, and the assessment is made on that basis. Any delay to the Completion Date is assessed separately under clause 63, and that is a job for your planner.