What does NEC4 clause 60.1(4) mean?

Clause 60.1(4) covers suspension and Key Date changes. The event is that the Project Manager or the Supervisor gives an instruction to stop or not to start any work, or to change a Key Date. Nothing in the paragraph asks why the instruction was given, so a stop instructed for the Client's convenience or to allow a survey is within it on its face; the check on Contractor-caused stops comes at clause 61.4, where the Project Manager makes no change if the event arises from the Contractor's fault. To rely on the paragraph the Contractor shows the instruction, that it came from the Project Manager or the Supervisor, what work it stopped or held back or which Key Date it moved, and when work was allowed to restart. Because the event arises from an instruction, the Project Manager notifies the compensation event when the instruction is given; if that does not happen the Contractor notifies under clause 61.3, and the eight week bar does not apply because the Project Manager should have notified. The change to the Prices is assessed under clause 63.1 as the effect of the stop on the actual Defined Cost of work done by the date of the instruction and the forecast Defined Cost of the work not yet done, plus the Fee. For a stop the effect is normally standing people and Equipment, demobilisation and remobilisation, and protecting partly finished work; for a Key Date brought forward it is acceleration resources. What most often goes wrong is that a verbal stop on Site is never confirmed in writing, so the start of the stop is disputed, or that the Contractor keeps a full gang standing when the instruction plainly allowed people to be redeployed and the Project Manager assesses on that basis. Any delay to the Completion Date from the stop is assessed separately under clause 63 by the programming expert.