Nokia 6 is receiving a new update, it weighs about 150MB. The update bumps the software version to 00WW_3_72A. Changelog describes that the update brings enhancements to the user interface and improvements to stability, no other details found. But after the update, Android security patch is updated to November 6th, 2017.
To check for the update manually going to Settings > Other > Software Update. If the update is not arrived, please wait for couple of days as the update will be rolled out in phases.