How do I go back to diamond?

I’m a newish ftp player and I just hit mythic but apparently because of the ranked rework I can’t progress till I get 12 level 11 brawlers. Is there a way I can tilt into diamond or am I just locked out of ranked for the couple months it’ll take to get all the coins

I’m a newish ftp player and I just hit mythic but apparently because of the ranked rework I can’t progress till I get 12 level 11 brawlers. Is there a way I can tilt into diamond or am I just locked out of ranked for the couple months it’ll take to get all the coins