OnePlus is pushing out an update to its latest flagship, addressing the screen flickering issue some people had and adding some other improvements, optimizations, and fixes. As always, you'll find the official changelog below.
I never had the screen flickering issue on my unit, but I've heard plenty about it. Basically, with auto-brightness enabled, if you went out in direct sunlight, the phone's screen would start flickering as it got brighter and brighter (95% or so). This wasn't a universal problem, obviously, but enough for OnePlus to address it. Good on them.
Left: Thanks for the screenshot, Andrew Champ
Another thing I'm excited to see is that there's an option to confirm your lockscreen PIN by tapping the checkmark. Face unlock and the fingerprint sensor are frustratingly unreliable on my OP6, so this is good. The other item to note is the improvement to HDR in the camera. OnePlus doesn't actually specify what is better in this update, so we'll have to take it at its word.
So far, there's no sign of the first Open Beta for the OnePlus 6, but I'm guessing that will be the first release of Android 9 Pie for the phone — one can hope, since OnePlus participated in the Developer Previews. That's pointless conjecture for now, however. Per the usual, the update will be rolled in a staged OTA or you can just grab it with Oxygen Updater. The downloads page doesn't have the OxygenOS 5.1.11 file available yet, but once it does, you can install the new version in recovery.