Hi Morgan, Many thanks. It seems to describe addresses on one side of Caerphilly Road from New Inn up to Hickmott Terrace, then cross over to Post Office Row. So I think P O Row might be the only building on the East side of the road, near the junction with Maes y Coed Road. (anybody tell me if I am wrong?)
Interesting that they don't call it "Old" Post Office Row, as in the census.
My ancestor wasn't there in 1914 but looking at the 1911 directory he is there, although they don't name Post Office Row, it is just part of Caerphilly Road.
Steve