In 2019, Samsung often released new Android security patches for its devices earlier than everyone else, including Google, and it seems determined to keep doing it this year as well. In Korea, Samsung is pushing out an update to the Galaxy Tab S3 that bundles the February 2020 security patch, two days before February actually begins.
The update comes with software version T825N0KOU3CTA1 for the LTE model of the tablet; the software version suggests the update includes more than just enhanced security, but we're unable to say what that might be at this time. It probably doesn't bring any new features, as the Galaxy Tab S3 has been on the market for nearly three years. Even security updates do not come out for the tablet regularly, only when necessary.
It remains to be seen if the February security patch will also be coming to the Galaxy Tab S3 in other markets soon, but for now, Korean users of the tablet can download the update over the air from the Settings » Software update menu on the device. They can also install the update by downloading the latest firmware from our firmware archive and flashing it on the tablet using a Windows computer.