bros some observation on the advanced formation
1) the mark in the formation familiarity is when you will unlock the formation trait for that particular formation
2) the level in the formation trait is determined by the number of players you have in your badge box with that formation (auto lvl up)
3) the formation is tagged to player. I got 4 of Cost 27 Lyon striker (couldn't bother to remember his name), all got the same formation
4) interestingly, after mixing (initially i have 6 of that formation, after mixing i am left with 2), the formation trait is still lvl 6
However, that could be attributed to the mastering of the formation. Not sure if it works if you mix before mastering the formation. Another question is if I got another player with that formation after I mixed, will it be lvl 7 or remains at lvl 6 (since theoretically it should be lvl 3)