Blizzard has shared a Blue Post, explaining that the Arena Rating Cutoff increase is accurate and the reason the cutoff is higher is likely from the weekly MMR Increase that was implemented last season.
We have seen some concerns regarding the Arena rating cutoff details and wanted to confirm that the increased values are accurate. We resolved an issue where the leaderboards were not updating correctly, it now shows the current season cutoff awards.This increase in the cutoffs in comparison to last season is due to weekly MMR increase that was introduced to the game. We are continuing to monitor the situation and will let you know if anything changes..
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