Somerset and Dorset Railway?

I cleared all the stuff off a shelf and found this. It's an original print, but unlike most of the postcard peddlers fare there is nothing on the back. I'm thinking early S&D with the 0-4-4, but can't be sure. Any clues?
The disc signal is prominent, but there is a standard semaphore in the background and it is unusually set away from the line so might be a bit of a red herring. New line, or freshly singled?


Update: I'm now reliably informed that it is Spetisbury on the SDJR c. 1900 during widening/doubling work. More below.
https://spetisburystationproject.wordpress.com/blog-3/page/2/