As of yet, not much real information in this topic... all assumptions for the moment...

Will be interesting to know what the real cause is! Malicious update, malicious dependency or a (long hidden) exploit or even an inside job?
I'm a long time user of Atomic Wallet and never had any problems. Their multi-coin and built-in exchange was their biggest pro for me. Used it just for playing with alt coins and pocket money.
I use the Windows desktop version (2.65.0) and haven't updated recently. I also didn't open the wallet recently, not sure exactly when I did last but surely it was more than 14 days ago. Checked my addresses via an online explorer and all funds were still there. Moved my BTC out with Electrum and moved my DOGE out with Coinomi. Beter safe than sorry!
Greets.