Robert Waterman says "My guess is just past Lymington Junction heading towards Brockenhurst in the 'up' direction. Also the section of line between Brockenhurst and Lymington Junction had the third rail laid as part of the Bournemouth electrification but due to the relatively low speeds allowed between these two points (60mph) did not get relaid with CWR until well after electrification had been implemented. Brockenhurst and Lymington Junction also retained semaphore signalling until at least post 1975 and I believe the signal arm shown was for the Lymington branch at the Junction itself. "