They closed the thread I initially started about this ongoing problem... AT&T 4G Trouble in Los Angeles
We (there are 2 BB Torch users here) still only run 2G in Los Angeles due to overcrowding - we have owned our BB Torch 9810's since September of 2011 and for 1 year and 2 months we have only run 2G during peek hours (Monday through Friday between 9am to 7pm.) We just lived with it, they tell me they are going to upgrade and fix the towers and they don't.
But the problem is AT&T pushed out an update to the OS and after updating we no longer have the option of selecting 2G - it's gone. So now the BB is a brick during those hours - it sits here doing nothing, and there is nothing we can do to fix it. Wifi doesn't work either because the BB has to "register" with the cellular network and when there is overcrowding it can't connect to register. Without 2G we have nothing.
3G and 4G LTE do work (I have a Lumia 920 here that runs the 4G LTE) it's just the 3G Plus (H plus) that fails due to overcrowding.
I demanded they break the contract when the BBX 4G LTE drops so I can finally get a Blackberry that can connect to the AT&T network - they said okay.
So if you are running 2G due to overcrowding in Los Angeles - don't upgrade to the new OS because it takes away the ability to select "2G."
Just thought I would pass along...