Nokia today announced that the company will provide Android Beta preview before the final update. Additionally, Android Oreo beta for the Nokia 8 is already live, so users could test Android Oreo before Public roll-out.
But, what about the Nokia 3, Nokia 5, Nokia 6, and Nokia 7? Well, HMD's Chief Product Office on his twitter handle announced that the Nokia 3 , Nokia 5 and Nokia 6 will be soon getting Android Oreo Beta. The recently announced Nokia 7 will be added to the list pretty soon.
Once you migrate to the Beta path, you will continue to receive Open Beta OTAs. You will NO LONGER receive the regular Official Stable OTAs.