The right hand signal post is cast concrete -from a very short lived GWR experimental phase before the adoption of tubular posts.
According to Peter W. Gray's "Steam in Devon" this location is Whiteball Summit on the Somerset/Devon border. The siding to the right of the main running lines was apparently laid in 1927 and Peter Gray believed the concrete slotted signal post probably dated from that time. The signal to the left is apparently the Burlescombe distant.

Shown as being from the 1950's I suspect that this must be a very late ' fifties date as 7022 " Hereford Castle " would have been a rare visitor to the far westcountry in the mid ' fifties , being allocated to 86C, which was Cardiff Canton , in 1956, and I cannot recall ever seeing her in or around Plymouth during that period in time (it went to Laira in Jan 1958 -Tony).
" Hereford Castle " did , however , have the distinction some years later of finding herself at Laira , being the last " Castle " to be allocated to Plymouth's Laira Depot after all that Depot's former " Castles " had been moved away in the very late ' fifties and early ' sixties , but she left Laira for Worcester in March of 1964 before finally ending up at Gloucester's Horton Road Depot in October that same year , the Depot from where so many " Castles " worked their last months in service.
7022 's withdrawal from Gloucester in company with 5042 " Winchester Castle " and 7034 " Ince Castle " on the 25th . June , 1965 just left 7029 " Clun Castle " as the last of the class in service