We’re a few hours behind on this one, but it looks like at around 1 PM ET time today, AT&T and Nokia began pushing out the Lumia Black firmware, which also has OS Update 3 on board. Indeed, a few people have chimed in on our forums and numerous tips have rolled in confirming that the update is now live.

Interestingly, the Lumia 520 on AT&T launched with double-tap to wake back with Amber. It was pretty much the only Lumia 520 to have it, though others have since received the feature since getting Black on other carriers.

Lumia Black includes some under the hood optimizations, Bluetooth 4.0 LE, camera improvements and greater support for Nokia software. Update 3 from Microsoft brings Driver Mode, custom ringtones for text messages, and the ability to close apps in the task switcher, to name a few.

To get the update, head into Settings > Phone Update > Check for updates. You’ll want to be on Wi-Fi and have your battery charged before the update. No information will be lost and it shouldn’t take more than 20 minutes. Once completed, you should be on OS 10521 and the Lumia Black firmware (found under Extras + Info).

Dive into our Lumia 520 forums if you have any questions or want to talk about the update!

Thanks, Nathan F. Topher J., and NYRBeezer (for the screenshots)