Reserve Teams move from league to U19 league

Hi, I started  creating db with polish lower leagues, and I've noticed a problem. Some Second Teams after a season or so, move to created U19 league. I tried everything what I could think of but it always end up same. Here how I built it.

So each team got created U19 Team and (most of them) II Team.

Each of the II teams are allocated in leagues.

And each of the U19 is also allocated in U19 League.

Each of the U19 divisions got type U19 Division

Rules are created as U19 Divisions

I've created U19 Cup for all those U19 leagues, and it seems II teams don't appear in it, as it is set as youth cup. They only appear (as soon as) after a season in U19 4. Liga. I simulated for a season few times and it always happens, and because I set leagues on fixed some of them don't play for a season or so (not enough teams). Whenever I set flexible with minimum and maximum teams needed, it's obvious, they are short. (Here 2. Liga with 16 teams instead of 18 as 2 of them were moved to U19 4. Liga)

Those II Teams always appear on this 5th tier of this U19 League I created (It's lowest ‘playable’).

It's only few of them that are moved (usually total of 7-9).

Does anyone got any idea how can this be fixed, so they don't get moved to U19 Leagues and stay in Normal Leagues? I'm just running out of ideas what else I could make/try to make it work properly…

I rebuilt the whole rules twice.

I experimented with type of the divisions.

I tried fixed rules as well as flexible with team min/max.

All leagues double-checked for teams needed.

What also let me think, but I don't know if it matters, when I convert to Advanced rules and test it, it always goes that U19 3. Liga is short of teams (common error what's weird without changes sometimes says 2 teams short, sometimes 3 or even 4), but teams got moved to U19 4. Liga. It tests completely fine on basic rules.

Wow! Now it's even 4 short, but did test on basic once again.

Anyone can help with it? Any ideas?

I think I might have found a solution to it. I need to run few more test and make it fixed amount of teams in leagues, but II teams don't move to U19 leagues anymore. Main leagues (especially the lower ones) just go shorter after a year, but I'll test min/max variations and make all divisions fixed as well as close the lowest inactive division, so the amount of teams in particular league is locked. So I think we can close this thread 😃😃…