Some years ago now I was nightshift on, IIRC Christmas Eve, with a major possession for bridge replacement somewhere between Gretna Jc and Carstairs, booked on as soon as the last train had passed, for the next 2 or 3 days. A storm then damaged the roof at Preston station, causing heavy delays, however the engineers insisted that the job start on time, otherwise it would overrun, and the last train could not therefore get beyond Carlisle. Virgin were unable to source any road transport, or hotels, for their passengers so with the support of the National Operations Control in London, the possession was indeed held off and the (very busy) train got through. We did all we could to assist the engineers by diesel-hauling the train from Carlisle, so that preliminary work such as isolating and removing the overheads could start on time. And, in the end, the job finished on time!