Known Bug or New? check_all_models() race condition

Hey Guys,
I’m new here, can someone help tell me if this is a known issue or a new bug?

Recently we had an issue with one of our developers writing a Django app that passed system checks when running locally on his computer, but not on another developer’s machine. It actually happens for me about 50% of the time! We are running Django 3.1.5.

I dug into it a bit and it seems like there must be a race condition between registering all the models with the app and the check_all_models() system check. I added a print statement to check all models printing the number of models and the models checked and it actually fluctuates for me each time I run manage.py runserver.

I tried to reproduce it in the Django tutorial and I could not reproduce it there.

I’m happy to dig in further if you guys think this may a bug, but I might need a few pointers.