Last I was down in New York (a few months back), NBC flagship WNBC-4 was still using "Newschannel 4" as the title of their newscasts.
It's entirely possible that the newscasts may still be titled "Newschannel 10", but with reporters ending their stories by saying (as an example) "Live from Providence, I'm Joe Doakes, NBC-10 News".
After all, ABC's evening newscast is titled "World News Tonight", although correspondents end their stories with a tagline like "From Washington, John Doe, ABC News".