I'm stunned that people think that taking out a major phone exchange, plus internet backbone, is somehow a "distraction" or "not important enough." Oh, yeah, and 911 service is down for hundreds of miles? Nahhh, not important enough.

This sounds like somebody wanted to attack communications, and they did. The "warning" was basically useless, and only spared the lives of the nearby apartment dwellers by luck -- because 6:30 AM is a time when you would expect everyone to be sleeping in (except maybe kids opening gifts), and you would expect them never to notice the "warning" until everyone was dead.

Possibly it was a grudge against AT&T or someone who worked at AT&T. Possibly it was a direct attack on communications and an attempt to spread terror, as well as ruining Christmas. There's a slight chance that it was intended to kill some particular person in the apartments, and cover it up with a pile of bodies.