I’d need to test or scour the code to see what that issue might be, which is beyond what I can do for free. I’m pretty sure that
first_day applies to just that, but I don’t really know.
My hunch is that the TL0 restrictions are your problem.
The problem that people most often complain about is that the new user restrictions are too restrictive. Unless you think that your learners are really spammers, holding them back to TL0 is probably a mistake, and that whatever you’re trying to do might be better solved with badges and group permissions.