This account was already banned for me back on Feb 13, but then it got banned again on Aug 5.
This further proves that A\ bans accounts based on association. The link between these two accounts of mine is probably the IP and machine ID.
So if you’ve ever had an account banned by A, you definitely need to change your IP. If you can’t change your machine ID, you can run things in a virtual machine. I use WSL more often, so just starting up another WSL environment works fine.
I really can’t figure out A's account banning logic, but it seems like they look at email reputation. I noticed my older accounts with higher reputation never got banned, but all the new ones I created were banned.