File this one under hopeful, but AT&T via their support forums have confirmed that the Windows Phone 8 GDR2 OS update and accompanying Amber firmware from Nokia has been cleared for the Lumia 820 and 920.
ETA? Tomorrow, October 10th.
Now we should be clear that this isn’t an AT&T or Nokia press release and Nokia’s own webpage has not yet been updated to reflect this news (it still says ‘waiting for approval’). However, a Community Manager did post the information, and it seems too detailed and confident to just be a rumor. Indeed, the Community Manager is an employee of AT&T so it has some credibility to it.