Samsung has used its Developer Conference 2018 to introduce its next generation custom Android 9 Pie-based user interface design. Dubbed One UI, the new interface has been designed to simplify the user experience by reducing clutter.
https://www.notebookcheck.net/Samsung-shows-off-its-new-One-UI-interface.357731.0.html
Sigh, this site is going down the sh!ter.
How on Darth is it unclear when this will be released, if Samsung representative specifically stated "January 2019, on S9, S9+ and Note 9"