Samsung is rolling out stable One UI update for Galaxy Note 9. A two week ago Samsung has already rolled out One UI stable update for Galaxy S9 and S9 Plus users. This update is currently rolling out in Germany, it may come to other countries very soon.
The software version is getting bumped to N960FXXU2CRLT in Germany, which may also be expanded to other countries later on. The new update also brings January 2019 security patch. The size of the update is 95MB.
If you are still waiting, you can download the newest update build by going into Settings > Software updates and tapping on “Download updates manually”.