Is it possible that the A330 replaces smaller aircraft on shorter routes?

Any time they did charter flights (usually a supersonic run out over the North Sea/Atlantic/Bay of Biscay and back) out of regional airports on the BA Shuttle network. It would be a surprise for Shuttle passengers when they arrived at the airport. Also back in the old days of Hawker Siddeley Tridents, BA promised that if you were at the airport 10 minutes before the scheduled time, you would fly, even if the schedule aircraft was full. They normally had a spare Trident on standby at each airport for exactly this purpose. But sometimes they would have to scramble to find any available aircraft and at Heathrow very occasionally that meant a Concorde. This was in the old days when flying was still dominated by flag carriers but they were beginning to face intense completion from independent airlines. In particular British Midlands started competing directly on Shuttle routes, forcing BA to finally upgrade their no-frills Trident service. The new Super Shuttle service used 757s with a hot breakfast in the morning and free food and beverages on later flights. To really launch the new service though they laid on 3 Concordes for LHR-GLA on the first day.