After manually rescanning for channels, it's all back now.
You are so lucky to receive cable channels with an antenna. I'm moving to your area! 
Good thing I caught it when I did, otherwise it would have continued that way another 3-4 days until the HDHR Prime did another background channel scan.
The sympton was all my cable channel recordings were missing from the schedule.
Looking in the log I saw that this mornings guide update didn't get EPG for my cable channels.
In fact it had deleted the scheduled recordings, log was full of lines like this
[DVR] Deleting job with expired serial: 1688608800-21 Viewfinder (EP011788090192)
I was going to do a delete and recreate guide database and that's when I saw the image above.
Now is a good time to advertise my script. 
You would have been notified as quickly as you want (you can choose how often the script checks for lineup changes in your sources). Just saying. 
