I don't quite understand a few things about what's happening when I interrupt a repeat timer via the yellow button in the 1 or 2 seconds before it is starting.
Why can't this situation be handled like a recording that has actually started and been stopped afterwards?
Now the situation is like this:
The red recording symbol is on although there is no recording going on.
The tuner that was supposed to be used for the recording isn't released.
The timer can't be reactivated via the yellow button on the same day.
So without at least a GUI-restart there's not much that can be done to get the tuner back.