Not sure about 1939 but I can tel you that Sunday newspapers were certainly being delivered door to door in the 1940s. I know because i was a newspapers delivery boy in Tintagel n the late 1940s. This pratice stopped i believe in the 1970s.
Daily papers, to my knowledge, have never been delivered door to door & Cooks newsagents, used to deliver by van to certain points each day.This stopped to most people around a year ago but I believe that certain places still have a delivery to a central point. And contrary to your implied suggestion that we don't read papers in Tintagel, you are way,way out. Sales of daily papers has always been good despite the fact that you to go & collect them!