Yep around here we tend to add extra insulator supports for later upgrades, my signal was also on a temporary span wire so it has the span wire hangers.
We don't use the grey backplates but for some reason when they did construction here in 2005. They were grey eagles but they should have kept the grey backs
I guess they might have been York Region take downs that the contractor reused for the temp lights. I sometimes see older lights like yellow backed lights and metal lights used for temp signals here.