AT&T's LG G4 nets several improvements following OTA update
Before you start the process of updating your phone, you should make sure that you are on a Wi-Fi connection. In addition, your battery should be charged to at least 50%. Keep in mind that because the update is being sent out on a staggered basis, not everyone will receive it at the same time. You might have to wait several days for it to hit your handset. You can try to manually pull it out by going to Settings > About phone > Software updates.
With all of the improvements and enhancements coming with the update, your AT&T branded LG G4 is going to feel like a new phone. Feel free to let us know what changes you've experienced after installing the update, by commenting in the box below.
source: AT&T via AndroidCentral