Now it is probably safe to assume that the Android 8.0 Oreo update will be skipping the phone, but the good news is that if you’re still using the handset and would love to see the Oreo update, XDA senior member Agent_fabulous has managed to take the Oreo AOSP and create an unofficial and experimental build for the phone.
However given its early development, it is not recommended that you use it for your daily driver, but rather it should just act as a preview of sorts for users to get an idea of what they could expect should this experimental ROM ever be completed and released to OnePlus One owners. So far the list of what’s working includes key functionality like WiFi, Bluetooth, RIL, audio and video playback, NFC, and so on.
Other features like the camera and camcorder have been disabled. If you are interested in taking the ROM for a spin, then head on over to the XDA forums for more information regarding the build and how to download it.