A couple of days ago, my recordings of NYPD Blue on H&I quit working. I looked at the Guide and found that the Guide is now for Telemundo. For 2 days now, the guide is for Telemundo, but the shows on channel 383 are still from H&I. This looks like Telemundo will be taking over channel 383, but no word on where H&I will be. Voice control gives channel 383 for both commands "H&I" and "Telemundo". I wish this process was a little more organized so that we users can track what is going on.
For now I would just use the cable-remote to enter the channel, or the linear channel list.
H&I and Telemundo are broadcast networks. Most likely the broadcast station carrying it is making changes. Comcast just passes the signals on.
Where are you located, and what broadcast channel is carrying it? There should be station ID near the top of every hour.