Source:
WG on Aug 3rd will uban any player who recieved a chat or account ban prior to March 24th 2020. This comes with a few caveats namely if they break any rules and are caught they're back to being permabanned.
As for account bans it will only effect accounts that did the following to get banned.
Partaking in contractual battles (when two or more players negotiate and engage in a battle with a predetermined outcome) ~Basically rigging a match for PMs, clan wars, rampage mode, etc
Selling accounts (only cases with chat bans; those banned from the game do not apply)
Destroying allied tanks (teamkill)
Nicknames that violate the game rules
Flooding and advertising in the game chat
Insulting players and administrators in the game chat
Players who committed the following acts won't be unbanned.
Various legal violations ~Basically breaking any laws in their respective regions.
Fraud and spam ~
Botting (creating and controlling bots imitating human behavior)
Use of prohibited mods
Threats of real-life violence
Doxing users ~For those unfamiliar with this it is revealing private information of someone else with the intent of wish harm upon them. Its HIGHLY illegal in many countries can result in legal action against the perpetrator.
The tl;dr version is that 10 years worth of asshole players are about to get unbanned and the toxicity levels are likely to be at an all time high. WG you've really outdone yourself with this decision and that is no easy feat given your stupidity.
Source: https://www.reddit.com/r/WorldofTanks/comments/i0xw7q/lots_of_players_are_about_to_get_unbanned/