There are many glitches with TIVO software, like on TODO items where sometimes it says how long the recording, while other times it won't tell you. I also get a kick out of it when I set up a recording on a different Tivo than I am using, and it tells me that "Recording Started", even though the schedule is for a week in the future!
But... this time, it's a real mystery. On one of my Premiere Tivos, the guide is not missing any titles from 8pm on Wednesday 4/15. On the other one, the guide has all kinds of "new" showing and otherwise blank on many channels. I keep doing network updates, but it doesn't change anything. Anyone have any ideas? I've had to tell it to record these blank "new" time slots in order to get the upcoming next episode.