I had similar problem. My rank never reset. I stayed in constructed Mythic. Also not receive any of the End season Reward, no boosters nor card styles. Originally the Play-In points for finishing Top 1200 were also missing. Then when I wrote the first time they awarded them, but also give me a Qualifier Weekend token, the one I shouldnt have because that is for Top 250. Now they keept telling me the team is informed and to write here so more people could know about the issue.

Same issue. So basically people who have limited time to spend on the game (due to work) basically just got locked out of reaching mythic this season. So not only will they not get the same amount of boosters, but even worse if they wanted to reach mythic for qualifications and such they can't.