I play to pass the time and have fun, so I played Russian with a 4.0 tank lineup. I started noticing that the matches were getting harder, and then I realized I was uptier I then switched to a 4.7 tank lineup. At first, everything was fine, but after a week, I was uptier again. I switched to US tanks, first playing a 1.0 lineup because I had never played in that country. I soon started playing uptier. I moved to a 2.0 lineup, played for a few days, and then uptier.
I returned to Russia with a 3.3 and 3.7 tank lineup. After a few uptier matches.
Why do they put me uptier wherever I go?
It’s just the way the matchmaker works. You can hover over your teammates name in the list and see what the max will be by viewing a few of them. Uptiers are not always bad, just ensure that your tank lineup is all at the same BR or close, as the highest one on the lineup is what the matchmaker uses.
Just a part of the game, matchmaker gives you 1.0 BR leeway. I found that constantly worrying about uptiers made it harder to enjoy, most vehicles can do well in an uptier if played properly.
Also at certain BRs there are more uptiers than others. I don’t know every BR that is likely, but I know that 5.7 is almost guaranteed to be a 6.7 uptier. Same with 6.0 → 7.0.
After playing the game for awhile, from experience you’ll come to understand that some vehicles will perform better in the uptier than others.
That’s because Gaijin being Gaijin has pushed some vehicles to their current BR where they can barely deal with the vehicles that equal that BR. Others have no issue.