Yeah there wasn't a lack of options for fail over. I suspect there was a lack of care to plan or test for them by many parties. Regardless, I personally have backed off really blaming bell for this one other than the cell towers going down. If you can't happily lose a campus for a week, it's the design that's the issue, not the non infinite uptime of the campus.
The folks on this list likely know where the central Tennessee backup
tandem office is located. Although its semi-public knowledge, I avoided
mentioning its location until the immediate threat passed. LATAs don't
have much legal meaning anymore, but every LATA had at least two tandem
offices.
Nevertheless, the "cloud" still depends on physical infrastructure.
I'm sure there will be several investigations by regulators why all
the 911 PSAPs didn't fail-over to the backup tandem office. Of course,
single-homed circuits physically connected to the Nashville CO wouldn't
fail-over.
Amazing how much data is in LERG.
-Nathan