[Update: Sprint is also rolling out the update, but there is only December 2018 security patch. The size of the update is 196.05 MB. The software version is N960USQU1ARL1]
T-Mobile is rolling out a new update for SamsungGalaxy Note 9 which brings new security patch, enhanced calling feature and camera improvements.
This update brings Camera preview improvement along December 2018 security patch, providing fixes to 40 Samsung Vulnerabilities and Exposures (SVE) items.
It also includes New Calling Service Enhancement – Caller Verified (Stir/Shaken) simply known as a caller ID and scam protection feature from the carrier.
The Galaxy Note 9 is receiving this update as the build version N960USQU1ARL1. If you want to check this update manually, head into Settings > System updates > Check for system updates or you can simply wait till the update automatically appears on your phone.