Yeah, that happened to me last time. If you go down to 30 users, it will let the 31st user join any team. But if you try "Creating a new Character" you get stuck in a limbo where the game thinks you are in the league, but you also can't access the league.
But I don't want to confuse the issue. Maybe if we provide a template for them to test this it will help? (if they even read this)
1) Create a league that allows custom coaches (Any, Coach Only, Coach and Owner)
2) Have 32 unique users take all the teams and create "Custom Coaches" (This is very important!)
The reason we do this as 32 man CFMs is that it makes every coach start on an equal level. If we don't, people like the Seahawks will have a coach with a lot more unlocked coach tree options
3) Sim a week, have a coach retire and replace him/her with another user who makes a custom coach (This might not break it the first time, don't think you have the bug fixed if it allows a user on your first try)
4) Sim another week and have a user kicked by an admin. Have another user try to log in and take that team (again custom coaches are key).
5) Do this a few more times and I pretty much guarantee that you will see the issue. It has happened multiple times in 2 of my leagues now
Some thoughts you can take or leave -
-I'm in another league that started pre (before the) scouting update. They voted to not reboot to take advantage of the scouting changes. They have not seen this issue even though people come and go pretty steadily
-Could there be a limit on the number of coaches allowed in the game? At start, there are at least 32 coaches on each team. When one of these franchises starts up, 32 coaches are fired and 32 custom coaches are created. That's 64 coaches in the league now. Post update you also have 32 offensive coordinators and 32 defensive coordinators now as well. That's 128 total coaches. I know there are also a few other random coordinators to hire from as well. If there is a limit for coaches, are we bumping up against it?
-My two league do custom draft classes. I don't see what the connection could be, but it's worth mentioning as I don't know your code base.