https://worldoftanks.eu/en/news/general-news/preferential-matchmaking-fixes/
According to WG they realized they were making a mistake by trying to change the pref MM tanks to regular premium tanks. So preferential MM will be kept but those tanks will be buffed to fit better the meta. (Lol FCM mobility and Type 59 buffs)
Also they are studying a new algorithm to fix the MM:
"In its current state, the matchmaker often fails to ensure proper rotation between the top/middle/bottom of the list. Getting matched at the same position for several battles in a row slows down progression and degrades the overall experience for absolutely all vehicles. Unfortunately, simply tweaking the current algorithm won’t fix it.
We tried to artificially lower the probability of getting preferential Premiums in +1 Tier and same-tier battles. However, this created more problems by increasing the number of single-tier battles and waiting times for not only Tier VIII and IX but tanks tiered VI-X.
So we’re looking into redesigning the underlying matchmaker rules to improve 3/5/7, 10/5, and 15 template distribution. This will aim to prevent cases of spending 80% of in-game time in 3/5/7 battles at the bottom of the list.
As you can understand, to find the optimal solution will take some time (about half a year) and we ask for your patience. We have already laid down a plan and work on the matchmaker is underway. We will give more information when we have it in a separate article, so keep an eye out."
Let's see how they will fuck this up.