Christmas has come early for some Samsung Galaxy S9 and S9+ owners. In a surprise move, Samsung has today released its Android 9 Pie-based One UI update for both devices in certain countries. One UI is available now as an OTA update in Germany, Italy, Switzerland and the UAE, according to SamMobile.
https://www.notebookcheck.net/Samsung-has-begun-rolling-out-One-UI-to-the-Galaxy-S9-and-the-Galaxy-S9.386411.0.html