New Mini Cup format: questions!

I am trying to wrap my head around the new "Mini Cup" format. Any insight you have will be appreciated :)

If you click "tournaments" then you click "tournament calendar" at top of page, it takes you to a LG-Doc that explains ladders, mini cups, waiting room, etc. Here is what that Doc says about the new "Mini Cup" format (which I believe started sometime in 2023?? replacing the old "Monthly Cup" format)

"Mini Cup
The Basic Round tournament starts immediately when three players are entered. The group tournament is played as a double round robin. Players scoring more than 50% of the possible points will advance to the next level.

"This is how it continues. A player can play any number of tournaments. If a player advances to a level where they have already secured promotion, they will only play in one tournament at that level. However, if a tournament has already started at that level, the player has earned the additional right to play at that level."
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(that last paragraph is confusing...not sure I understand...)
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Questions:
1) When you advance to the next level, do you have to register for the next level tournament, or is your registration automatic?
2) If it is automatic, do you have the option to drop out?
3) I am on level 2 for Fendo Cup. I am one of FOUR ready players. So my question is, what triggers the level 2 tournament to begin? Do the four players need to do something first?
4) Is there a limit on the levels? Currently I only see 1 or 2 or 3 levels for most games. Has anyone seen a level 4?

If you have any knowledge, please share (or if you can think of more questions, please ask)

If you advance, registration should be automatic, and you can drop out on the Tournaments page. It's mostly the same as the old monthlies.