OnePlus devices won't support Project Treble, Android's easy-update feature
http://www.techradar.com/news/oneplus-devices-dont-support-project-treble-androids-easy-update-feature
"We are not currently supporting treble and do not plan to for these devices," Krisko said.Google's Project Treble makes it easier for Android owners to upgrade their devices to the current version of the mobile operating system, which likely means that the lengthy waits Android users have endured while manufacturers roll out their own updates may be a thing of the past.
Yet that won't be the case if you own a OnePlus device, at least for this year. In an AMA held yesterday on the OnePlus forums, representative Adam Krisko confirmed that none of the company's currently released devices support Project Treble. Nor will they in the future.