I actually think it would be this....
DBSO, Mk2 test vehicles and 37682
The train worked an out-and-back trip along the Durham Coast over two evenings (Out 3Q20, back 3Q03) stabling at Heaton T&RSMD in between.
Hope that helps
What exactly does the Measurement Train Measure?
Yep, you are most certainly correct, the New Measurement Train HST has a booked "as required" path up the Durham Coast on a Saturday that passes through Sunderland at about 12:15 northbound which it uses periodically.No, it wasnt that train in your flickr picture mate, it was definitely a Yellow HST, it passed the place where my mam works(Ryhope) around 12-12:30, I did try and get a picture of it, but by the time phone camera sorted itself out, it was gone...
I saw it through Potters Bar yesterday at about 8pm, second time I'm seen it around that area in two months. Gets around a fair bit!