I was one of those hacked. I always use atomic wallet on a dedicated laptop that is not used for anything else other than a wallet. I couldn't get my EOS to send, so support recommended I download the wallet to another device and I did, to my cell phone on May 31, from the Apple store. I believe that my account was compromised when I entered the seed phrase on my Iphone. What do you think?
Sorry for your loss, but downloading the same Atomic Wallet software into another device couldn't have helped to protect you, that is because with the number of Atomic Wallet users who had their wallets compromised, it surely wasn't a local issue, but one that was wrong with the Atomic wallet software.
You should have used your seed phrase to import your wallet into a recommended software like Electrum, and send your funds immediately into another wallet with an Electrum seed phrase. It is going to be difficult to know exactly why you were hacked because even Atomic Wallet haven't provided an update on what caused the multiple attacks to their customers. Don't use closed source wallets, use open source wallets like Electrum, Sparrow or BlueWallet, or open source hardware wallets to store your funds.