When Patch 21.4 first launched, a bug was introduced that caused some players to get their rating reset to 0 (even though it shouldn’t have happened). The bug was quickly fixed, but as it turns out, it has introduced another one that caused those players to ghen gain more MMR than intended for wins.
The fix to the second issue just went live, and the MMR of players who were affected by it in Top 10% of MMR was reduced to adjust for the unintended extra gains. The reason is that some players got pretty high on the Battlegrounds leaderboards “unfairly” (but not by their fault) by getting more MMR than everyone else.
Read more in the official blue post below:
Last week’s patch introduced a bug that unintentionally caused people who played Battlegrounds immediately after the patch to have their rating reset. We quickly squashed that bug so that no more players would have their ratings reset in this way, and, at the same time reset the affected players’ rating to what it was just before 21.4.
Unfortunately, this introduced another bug that caused them to gain more rating than intended for each game following the initial fix.
Tomorrow, we will be implementing a fix that will stop players from gaining this unintended bonus rating. For the top 10% of players who benefitted from this bug, we will also be reducing their ratings to adjust for those unintended extra gains.
We will update this post once that change has gone live.
Update: This patch has now gone live in all regions.