This is a wild perspective that is probably true in cases of smaller companies or instructions directly from poor ownership and inexperienced managers.
Managers that allow or encourage people to work off the clock in most cases are putting themselves at risk. God forbid somebody get injured or contact the department of labor. Great way to lose your job.
Sounds to me like she’s been given an order to cut overtime, which is going around at so many companies recently, and she’s probably stressed because the situations that OP describe make that very difficult.
Makes sense that she was going through picking jobs and cancelling them while trying to find something that would fit the reduced timeframe. Ultimately sounds like that wasn’t possible. Unfortunately it also sounds like she is unable to effectively communicate this to her leadership or has already tried and been dismissed.
OP, I’d recommend trying to express to her that you understand she is trying to abide by the directives given to her, share with her that you are also, and see if you guys can work out a better plan. Maybe encourage her to share the issue with leadership if she hasn’t already. Might be smarter to not assign any jobs post 16:30 and just eat that half an hour if the people above her aren’t looking. Maybe less gets done, but then she’s not getting in trouble for OT. Unless she’s the owner, safe bet that her emotions stem from the emotions above her or fear of repercussions to her own employment. That or she is just inexperienced and hasn’t yet learned what all middle managers eventually do, it’s somebody else’s money
This is great. If I can dumb it down a bit here, instead of trying to get someone to step out of those emotions just step in with them.