LG G6 units on Verizon has received Android Oreo update recently and now LG G6 devices on Sprint has also started to receive Android Oreo update. Update brings the May 2018 Android security fixes and all the goodies from Android Oreo. Update weighs around 1.8GB in size.
Changelog of the update detailed as Updates the Operating system to Android Oreo 8.0, Optimizes performance, and May 2018 Android security patch. Recently LG G6 units in Europe has started to receive the Android Oreo update. You can check the update manually in Settings-> Software update. Update will be rollout in phases and it will take couple of days for the update to hit all the devices.