Good news: AT&T revealed today that it will begin delivering the long-awaited Microsoft GDR2 and Nokia "Amber" updates for Windows Phone 8 to Nokia Lumia 820 and 920 handsets starting tomorrow, October 10. An unspecified error prevented these releases from shipping more quickly, though many users have incorrectly blamed AT&T for the delay.

"AT&T has completed testing the Nokia Lumia 820/920 Windows Phone software update on our network," an AT&T community manager writes in the AT&T Support Forums, a post that was first discovered by WPCentral. "We expect Microsoft to make the update available beginning 10/10. When the software update is available for you to download, Windows Phone will notify you so you can download it directly over a Wi-Fi connection. We appreciate your patience."

GDR (General Distribution Release) 2 and Amber originally shipped to customers in August, but those with Lumia 820 and 920 handsets on AT&T here in the United States immediately noticed they were stuck in "waiting for approval" purgatory with no word when that would end. Nokia originally said that they expected all Lumia users to get the updates by the end of September, but then had to adjust the time frame when that date came and went.

In case you're not familiar, GDR2 is the second major update ("Update 2") for Windows Phone 8. You can learn all about this release in my Complete Guide to Windows Phone 8 GDR2.

Nokia "Amber" requires GDR2 and adds some Lumia-specific enhancements. I've written about this update in a few places, including Lumia 1020: A Peek at GDR2 and Amber and Nokia Brings Amber, Pro Camera to More Lumia Handsets.

So good news!