With the update 2.9, WoT Blitz will recieve something not yet seen in WG’s titles (EXCEPT WORLD OF WARPLANES) – a +-1 matchmaker.
This kind of matchmaker was already tested on the NA region, and will now make it to all servers in the upcoming patch. The official statement as of why this is happening is that “it will correct the balance of vehicles sticking out statistically and improve premium vehicles which had beneficial matchmaker”.