Why no motion of all coins from the hot wallets to cold, as a security precaution?
Has this been done?
This would be the first move to make if keys are compromised.
If we think about it, whichever wallet was compromised would be emptied; for example why would the hacker get 1000 ETH if the wallet had 2000 ETH?
So what's stolen is stolen. I don't think it's possible to hack a new wallet while the exchange is not operating.