Now AT&T has joined the list. The company has started rolling out the One UI 2.0 update based on Android 10 to Galaxy S9, Galaxy S9+ and Note 9. A twitter user by name David Watt has tweeted that he has received a major update on his AT&T Galaxy Note 9. The update brings the latest January 2020 security patch update to the device. The build number of the new update is DTA4. The update size is around 2061 MB. Not only that many users in Reddit also posted about the latest Android 10 update.
Along with the Galaxy Note 9, the AT&T Galaxy S9 and Galaxy S9+ have also started getting the latest Android 10 (One UI 2.0) update. This is also confirmed by a Reddit user very_moist_water who has posted his Galaxy S9 screenshot. The update is around 2GB in size and it brings the latest January 2020 security patch to the devices. The build number of the firmware is DTA5. Many AT&T Galaxy S9+ users have also commented on his post that they have also received the same update.
You can manually check for the update from Settings > Software update >Download updates manually. If there is no update showing on your device, then wait for few days for the update to come to your device as it is being released phase-wise manner or you can manually flash the full firmware using Odin Flash Tool.