With the 1020, the 925, the 920 (now the "budget" WP8. Hard to fathom), the 8X still in 2 sizes, and the 15XX Phablet on the way, I have heard the same thing. I do not see it on the AT&T website anymore, which doesn't bode well.
As for support, all you can do is send emails or go to AT&T.com and open a chat to find out. AT&T is not exactly known for after purchase support of any device, including Android. They did a good job with generation #1 of WP7's (Focus, HD7s, Surround and the others), but the second generation (Focus S, Titan and Titan 2, Focus Flash) was left completely out in the cold except the 900. Throw in the 820 was not a real good seller as the lower end 8X and the 920 both sold better and I am hoping for the best but not expecting much. To be truthful, when I needed to replace my Focus S the support issue was the main reason I stuck with WP7 and got the L900. It and the 820 were in my price range, but I did not trust AT&T to release updates. I am sure Nokia has them ready, I just am not sure AT&T wants the headache.