Traditional procurement: architect as CA, design team conflict

You are the architect on a £2.8m secondary school extension under a JCT Standard Building Contract 2024 (SBC/Q). You have been appointed as both lead designer and Contract Administrator under a RIBA Standard PSC 2020. The structural engineer (SE) is appointed directly by the client under a separate appointment. During Stage 5 construction, you carry out a site inspection and discover that the contractor has formed openings in the primary structural frame at high level, work you did not authorise. When questioned, the contractor produces a written instruction signed by the SE directing the additional openings for mechanical services routing. The instruction was issued directly to the contractor without your knowledge or counter-signature. You also discover that these openings, if formed as instructed, will significantly reduce the load capacity of the frame at a key transfer beam. Your drawings show no such openings and your specification requires all structural amendments to be coordinated through you as CA. Two days later the client calls. They are under pressure from the school governors to complete before the autumn term. The client says that if you cannot accelerate the programme by four weeks they will consider exercising their termination rights under the contract.