I met a woman Thursday night who had taken an Avanti northward on Wednesday and southward on Thursday, and in both directions the train "reversed in a cul-de-sac" somewhere between Carlisle and Glasgow. The southbound train was on time at every station apart from 1 minute late at Oxenholme - I don't know about the northbound. Is this common, and do all of the timetables allow for it? Where might it have been? Note: I definitely mean Glasgow and not Edinburgh (where a reversal at Carstairs would not have surprised me).