There is some memory/garbage collection issue on the old TiVos (S3 OLED in my case, but I'm sure TiVo HD is similar)LOL - I was out of town Thursday, Friday, and came home today and found new season pass related recordings from last night. Looking at the to-do schedule shows all the season passes scheduled properly now. Seems like things are working for the time being, I'll keep watching the todo for signs of the problem.
In the end all I can think of was fixing S03, and then letting it idle for several days.
Must have needed a vacation or something.
When you have large guide data downloads it can't complete the processing.
This happens more often when
1) you use a provider like Comcast with huge guide data sets. Comcast duplicates all their HD channels in the 1xxx channel number range, which is roughly 50% more guide data. I never had an S03 error until Comcast started with the overlaid channel #s. I've heard anecdotally that DirecTV users had S03 problems in the past on S2s
2) you lose connection for multiple days. Often your system can download and process the full guide data on the initial download, and then incrementally take care of one days data. However if you lose connection for a few days, the guide data set becomes larger and it triggers S03 error.
Sometimes if you get S03 error, you can connect over and over again giving about an hour to process some data and the connection will progress a few percentage further, and eventually complete.
Sometimes that doesn't work.
If it doesn't work, the best, and IMO only, way you should resolve is to do Clear Program Information and ToDo List. Other methods run a HIGH risk of getting into an S03 initial set up loop that you cannot exit until you complete the setup, which you can't because of the S03 error on initial setup. Your solution if get stuck in that loop is probably to reimage the drive.
As to your ToDo list, keep in mind this is likely a separate issue that is related to your S03 issue.
Sometimes when you are encountering an S03 issue, you might have network issues that caused the S03 issue to start with. This may have prevented your unit from connecting for a while, like 30 days, and your TiVo has become inactive (even if it had lifetime or annual) and that would cause your ToDo list to not record.
Another common problem is after you resolve your S03 error, your TiVo downloads and process a lot of guide data. Even after the network connection is still needs to process the data further to get your ToDo list working, so I would wait 24hrs before thinking there is a problem.
You can also sometimes short circuit the processing and get it to process the ToDo list quicker by changing the ordering of your Season Passes. Just move one entry up in the priority order and save. It should force reprocessing right away.
I only glanced at your posts quickly, but I think you are right and the S03 error was the cause of all your issues to start with.
As an aside, I have an S3 OLED that I connect once a month. It used to be configured for Comcast, but I could only get the initial guide download and then the next month to work. After that it would be stuck in S03 and then I would need to do Clear Program Information and ToDo List, which takes a long time.
I switched it from Comcast to OTA and with the smaller guide data sets, I've never had S03 errors again, no matter how long I go without guide data and no matter how many times it happens.