Hi All, Last Sunday I flew into Heathrow after an overnight flight. The airline hadnt accounted for the clocks changing here before they do in the US, so we arrived an hour early due to that, and earlier still due to a good tailwind. Id allowed plenty of time for the tube-replacement bus to Acton Town before the tube to St P, but actually that ran every smoothly. All in all we ended up at St Pancras in plenty of time for the 13:05, let alone the 14:55 we had booked advanced tickets for. We got short shrift from the ticket desk when we explained and asked politely to exchange the tickets, so we waited patiently for the 14:55. In the event, due to disruption at Euston, the EMT trains were standing room only so we were glad of our reserved seats. However upon arrival at Leicester we were told we had to set swap, and this was presented as being for our benefit as the HST had an extra carriage compared to our 222. Of course all those who had stood from London quickly made their way across the platform, while our reservations were rendered useless as we struggled with our luggage. People were waiting eagerly for our 222 which made its way straight back to London. Upon leaving Leicester it was immediately announced that the HST was running on reduced power and we would be set-swapping once again in Derby. I presume one of the power cars was in-op but it still hauled us along reasonably well. I am suspicious that this HST had failed on its way south and so they swapped units in order to get the sick ship back to base in Derby, presumably avoiding the worst of the fines for late running, but perhaps also risk mitigating to be fair. Fortunately the numbers thinned out by Derby so I think everyone was seated by the time we were on our third set. We made it to Sheffield with around 25 min delay. What do the team think? Was it reasonable to cause disruption to a very full train, particularly invalidating the reservations of the planned EMT customers in favour of the diverted passengers, in order to mitigate delay of the southbound train? Could they not have simply sent the spare 222 down from Derby to replace the sick HST at Leicester, or was there not a spare crew for the ferrying? Or, have I interpreted the situation wrongly? Finally, is it universal that you cannot get an earlier train when on an Advanced ticket? What happens if the situation is reversed and your flight is late/you didnt know about tube replacement bus? Any leniency from the TOCs then?