Just a quick update. The bike went in for diagnosis and they didn’t find anything wrong with it. It behaved itself on the next ride and then went for its 600 mile service.
The following weekend we set off for an overnight in Moffat and the same fault codes occurred again. This time the “Transmission fault” wouldn’t reset and the quick shifter wouldn’t work. It lost ABS, TCS and the speedo. After stopping for a coffee and searching the Triumph forums, it seems like a dodgy quick shifter is a common failure and throws up the fault codes. Switching it off in the settings menu cures the other issues until shifter is replaced. Once I did this the bike behaved perfectly for the remaining 350 miles of the weekend and was really good fun to ride. It’s going into the dealers today for repair…..