Windows 10 on ARM devices with the Snapdragon 845 won't ship until the second half of 2018, according to Qualcomm. This is despite a version of the same chipset being available for high-end smartphones early in the new year.
https://www.notebookcheck.net/Windows-10-on-ARM-with-Snapdragon-845-not-due-till-2H-2018.272624.0.html