This road leads west and then north to Northiam. Is it definitely called "Northam Road" and not "Northiam Road"?

OS OpenMap also has "Northam" - perhaps this is the source of the OSM label, and it's possible the road name and town name have deviated organically over time.

Bing StreetSide has a signpost to Northiam, but I couldn't make out any road name signs. At least some businesses (e.g. Staplecross Pre-School Playgroup at St Mark's) use "Northiam Road".