I was on a service from Brum - Euston today and we got held up in the Wolverton area, didn't switch to the fast lines though until after Leighton Buzzard. We lost about 10 minutes and the guard didn't apologize to us.Our guard/train manager on the 07:30 Birmingham - Euston today made a big thing of apologising for arriving 7 minutes late at Euston due to the disruption today, not something that I thought was entirely necessary as our arrival time was little different to what it is about 50% of the time!
Other than a slowing of pace where we diverted onto the slow lines between Wolverton and Bletchley, there was little hint of the service being affected at all