Strangely, all the fibre cabinets here seem to be, deliberately, placed across the road from the original cabinet. Even on roads built with huge verges, BT seem to have deliberately chosen to cross roads.
For example,
This cabinet has its partner across the road, on the north-western corner of the T.
In
this example it seems to have been harder to site the fibre cabinet opposite, rather than next to the original.
It has struck me that both of these cases have put the fibre cabinet on the side of the road without a pavement - so it may prove to have been cheaper to run the fibre that side, even allowing for the cost of ducting across the road. That would imply that they weren't highly motivated to put the fibre down the existing ducting.