It is a fixed price lump sum contract under NEC3 option A. The starting date and the Completion Date were moved back by the Employer. I take it my price is fixed for the original Completion date. Can I claim for fluctuations for works that fall beyond the original Completion Date?
For any compensation event, you get to assess the impact of the delay against planned Completion. If you can demonstrate that there has been certain price increases as a specific result of the compensation event during that period then you can claim for this.
However - if the starting date and Completion Date have been moved before you signed the contract then that should have been agreed before you signed along with any increased costs. This is not a specific reason for something being a compensation event within clause 60.1