Ordnance Survey is great, but it’s not fast. Ordnance Survey’s Mastermap isn’t updated regularly enough to have captured the extension to my house, constructed two years ago. Hopefully, one day, the local planning authorities will find a way to connect their new construction sign-offs to those updates - a kind of bricks-and-mortar blockchain. For now though, if Mastermap isn’t going to put the right polygon in place, then I’ll have to learn how to do it with OSM. Perhaps the really neat and tidy areas of the UK OSM correlate to the hometowns of GI-related employees?