As an update I've surveyed the 2 near me, both were as accurate as anything else in OSM, maybe a few meters offset, but not noticeable. I doubt the location can be from post code data.

Unfortunately the charging stations lacks details about the ports, I could open the flap but none were labelled. Do you think I'm able to use NCR as a source for those details?

Local charge points: http://chargepoints.dft.gov.uk/api/retrieve/registry/format/json/postcode/PO36/dist/1/units/km/
Mapillary images should be processed soon.