We got reports from iOS users that the game performance got worse after the update, especially iPad users.
We are sorry for the inconvenience and would like to inform you that our development team is currently looking into this matter. We will release a fix as soon as possible.
On your side, you can try to restart your device and reinstall World of Warships Blitz. Also, some users reported lowering the graphics settings to the minimum and disabling 60 FPS mode helped them to get a better performance.