Sherlock Holmes: A Study in Improved Engine Green

As seen on ITV's 'Arthur and George', last Monday (16th March) - around 12m 50s into the episode, there is a singular occurrence which caused me to expostulate loudly and reach for my pipe.
Sherlock Holmes' creator travelled to Cannock, in 1906, in a train hauled by a SE&CR 'P' Class that wasn't built until 1910 (although it's clearly labelled 'LNWR', so maybe it was secondhand to the South Eastern? Or did Wainwright moonlight?).
Having eliminated the impossible, am left with the implausible: a very large dog had eaten Conan-Doyle's Bradshaw's...

 

Downton does the same thing (relettering SECR as NERC)

 

I spotted that, didn't believe dad when he said it had lnwr on it (I wasn't paying attention) adamant it would be secr!

 

Well, no doubt in a few years they'll be able to do all these scenes in the studio with CGI and get all the historical details correct. Until then we have to put up with the compromises they have to make by using what's available in reasonable reach of the studio and be grateful for their money, which we won't get when its all CGI.

 

Well, if 'call the midwife' is anything to go by, the CGI is even worse, as typing 'old train' into turbosquid tends to give you any old rubbish.