about 1 month ago - Smin1080p - Direct link

All vehicles in game are subject to Battle Rating adjustments. This has been the same ever since Battle Ratings were first introduced in update 1.37 in 2014.

No vehicle has ever been introduced, sold or rewarded with the promise that its BR and Economics cannot change. All vehicles are subject to these changes as they are dynamic systems.

This is covered by the Terms of Use and User Agreement (EULA) you agreed to both when creating your account and with every purchase.