Publicity and tens of millions in Bitcoin /Ethereum++ is a bad idea. Especially since once it's gone it's gone. Hacking your account means FU money and then some, with less chance of getting caught than other crimes. So they have all the incentive in the world to take heir sweet time...even if they lost 50% laundering, it's still more than enough.
I'm all for At&t to be held responsible if they broke security protocols. They charge an arm and a leg