I think reports have been exaggerated a bit! Yes, 55022 has put a leg out of bed. This hasn't happened once before - it occurred on numerous occasions in BR service, although it hasn't happened on the main line in preservation up to now. For anyone more interested in an explanation of what 'a leg out of bed' is, take a look at
http://www.ptfnasty.com/ptfDelticdisc.htm (in bold about 1/3 of the way down).
Reports that the piston went through the side of the loco are incorrect, although a few years ago, when 'thumper' put a leg out of bed its piston shot through the engine room window and ended up in a nearby field! Also, 60081 ended up with a large dent in its bodyside when something similar happened. 55022 has continued through to Edinburgh, but on one engine only, and arrived pretty much on time (thanks to a not so fast schedule). At Edinburgh, 40145 has taken over as planned, and I gather the 40 will work the whole tour over the next 2 days rather than being top/tail with the Deltic. Obviously the Deltic will now require power unit repairs before it can operate on both units, a major blow and bad luck for all those involved in its return - knowing many of them, I can imagine how they must be feeling.