The poles were going up in Sonning Cutting in September 2016, as evidenced in this shot of 66.155 working 6A03, the 04:45 Severnside Sita to Brentford Town bins, under the A4 bridges on the morning of 15 September.
PHOTO DATA FOR IMAGE 16-D-4751
camera : Nikon D610
lens : 70-200mm f/2.8
focal length : 98.0 mm
shutter : 1/800 sec
aperture : f/8.0
ISO : 400 ISO
original : Digital: 24MP NEF
SUBJECT DATA
Loco / Unit : 66.155
Train : 6A03, 04:45 Severnside SITA - Brentford Town Binliner