The Russian tech tree in 9.3 gets changes in 2 branches, namely the KV-1S split, resulting in a KV-1s on tier 5 without it’s top gun (which you will not get for free even if you own the KV-1S now) and the KV-85 which will replace the KV-1S on tier 6, keeping the top gun from the KV1-S but having other more “heavy” stats, resulting in what looks a bit sluggish compared to the old favorite.
The other 2 new tanks come in form of two new lights coming from the MT-25, the LTTB on tier 7 and the T-54 light on tier 8.
The tech tree will look like the one below and if you look closely you will also spot another misterious tank, the T-34-85M, which is currently in the supertest, but it’s ETA is currently unknown and hasn’t been mentioned for the 9.3 update.