Could be. I never got a notice the service was being canceled like the OP, but just haven't been able to sign on for a couple of weeks.The Direct Forum could likely tell you for sure.
Just got off the phone with Charter, service ended here (upstate SC) on 11/15. Charter no longer provides newsgroups. I kept getting the 480 authentication error. Sad to see it go. Any recommendations? As I dont have other source.
An excellent free *text only* news service is: »www.eternal-september.org/