This is from a Newspaper index hit in The British Newspaper Archive ( I don't have a sub currently to see full article) and describes the double fronted cottage, Brockholt (and fits with the 1939 Register)
Western Daily Press, Saturday 01 September 1945
... Hill, with good garden, containing 5 rooms occupied by Mr Robbins. Lot 2. The adjoining Doublefronted Cottage known as Brockholt,'' containing 7 rooms, let to the Postmaster-General as Telephone Exchange. Notice will be given for the tenancy this lot ...
Western Daily Press , Saturday 08 September 1945
... Sunnyslde. or No. 79. Almondsbury Hill, with good Garden, occupied Mr Rosser. Lot 2.—The adjoining Doublefronted Cottage. Brockholt, 7 rooms let to the Postmaster-General as a Telephone Exchange. Notice will be given for the tenancy of this lot to expire ...
Cheers
AMBLY