OnePlus just announced its new flagship phone. The OnePlus 5T comes with a Snapdragon 835, a 6-inch OLED, and... Nougat? Yes, the new phone is still running an old version of Android, but that will change soon-ish. In just a few weeks you could be rocking Oreo on your OnePlus phone, but the final release is still a few months out.
OnePlus discussed its upcoming software plans at the OnePlus 5T announcement. For those of you who will soldier on with a OnePlus 5, the Oreo open beta is starting later this month. For the OnePlus 5T, the Oreo testing starts later next month. These beta versions (OnePlus usually calls them "Community Builds") will be available for download, but you'll need to flash them manually.
As for the final OTA, that won't be available until 2018. OnePlus didn't provide a firm deadline, but it does claim "early" 2018 for the OnePlus 5. The 5T will presumably be on a similar timeline. The OnePlus 5T really should have Oreo, but at least the wait won't be too long. You can see the beta announcement in the above video at about the 1:30 mark.