Channel guide has a bunch of "To Be Announced" slots instead of the normal guide data

I was surprised when my Tivo Premiere didn't record the Tonight Show and the Late Show last night. So I looked at the channel guide, and I find in those time slots "To Be Announced". The complete description for the Late Show slot on CBS reads "(11:35pm-12:37am) To Be Announced * (CC, In Prog, SAP, Blackout, R)". Same is true for tomorrow and Thursday. Friday is slightly different - Late Show is there but Late Late Show is not. Next week looks normal. I looked around and found similar "To Be Announced" slots scattered around the channel guide, though most of the guide looks normal. What's wrong with my guide data and can I fix it? Is this one of those cases where I'm supposed to know to "repeat guided setup" or something similarly heavy-handed?

On a possibly related now, tonight's Jimmy Kimmel is labeled NEW, but my OnePass isn't catching it (it's not in my todo list or checkmarked in the channel guide).

I have the 20.6.1a.RC10 update and am on Comcast in the SF Bay Area.