Thanks for reporting this 
Judging from what you’ve described, this is some kind of scheduling task issues. Very similar to my topic from a while ago: Homework schedule system not working properly - Not exactly the same though, because the jobs are programmed differently than the general homework schedule, I guess.
In my case, playing through a few days up to a week somehow fixed the system. It performed a quiet reset and suddenly the tasks appeared at their designated times again. I haven’t found any other proper workaround yet, unfortunately.
Your one looks different. Bug that I encountered reproduces stably every time. I have been working as firefighter for 20 in game days, and it is the same on a different career ranks. Looks like a simple mistake from a game designer / tech designer, who chose the wrong time for the final job tasks appearance. In your case - I don’t know, as I don’t have in game kids yet to try doing the homework, but it’s a good thing that you found a solution for yourself! 
I tried to reproduce the bug with a brand new save file. Now I can confirm that everything happened exactly the way you described it: Daily tasks aren’t being refreshed after 3:30pm and the new tasks show up at 6pm sharp, when the work day ends. (Screenshots below for further dev clearance)
I’ll keep an eye out for this bug in other jobs + if it happens in new saves only or in older saves too.
EDIT: Do you still remember when you started the affected save file? This might make it easier to determine the in which update / patch the bug may be.
Hehe, congrats on a new job! 
Hmm, I started playing inZOI in late November and got the job as firefighter almost right away, so bug was since then.
I remembered that I once noticed this bug in Bliss Bay for Office Team Lead with a Zoi back from launch in March. I checked back (after not playing for a few weeks) and now the final set of tasks appeared at 3pm again. I think the bug must’ve been the same like the one you’re experiencing, even though I didn’t pay much attention to it then.
Have you tried to verify your files via Steam already? It might help to fix some scheduling issue like this 
If you haven’t done this before, here’s a short guide on how to do it: How to verify your game viles via steam
I’m about to check out the save file you uploaded (thank you 
), so maybe we can at least figure out if it’s save file or game related. I’ll let you know the results in a bit.
Save File Results:
After playing for 27 in-game hours, I’ve captured the following screenshots of the tasks throughout the day.
1: Starting the save with one task left at 3:25pm → no weird tasks showed up when ending the shift at 6pm
2: Beginning of the next shift, all tasks showed up right away
3: The second set of tasks for the shift showed up at 1pm → no weird tasks came up by the end of the shift at 6pm
→ When putting others’ save files into my setup, some weird timing issues can happen, so the tasks showing up early on day 2 isn’t that much of a deal IMHO. It shows that, at least for 2 in-game days, I was able to generate 2 working sets of tasks in your file which raises the chances that this issue might be able to solve itself in a weird inZOI way 
Please let us know if the bug is still occuring after verifying your files via Steam, like I suggested above. If it does, we can try (if you want) to swap the files again after I did 48+ in-game hours, so it may become stable again. Just let me know if that’s a workaround you’d like to try
