Neso cancelled a late Tuesday margin notice after agreeing to pay about £1,400/MWh for 1.7 GW of electricity imports from the continent on Wednesday evening, with the total cost expected to reach £10m — more than four times the usual daily average. The operator had warned of a 1,900 MW shortfall within normal safety margins, driven by extreme heat boosting air conditioning and fan use, low wind generation, and nuclear plant reductions in France.