"We are not currently supporting Treble, and do not plan to for these [OnePlus 3/ 3T and 5/ 5T] devices," writes OnePlus' Beta Programme Project Manager Adam Krisko in response to a query made during the Ask Me Anything (AMA) session on its community forums.
Launched in May, Project Treble is aimed to offer a modular base for Android to help device makers deliver faster software updates. It brings a vendor interface that separates the vendor implementation, including the device-specific, lower-level software written largely by silicon manufacturers along with some certain carrier tweaks, from the core Android OS framework. Once a new vendor implementation is designed, the fresh interface is passed through Vendor Test Suite (VTS), which works similar to what Compatibility Test Suite (CTS) offers for Android apps, to deliver forward compatibility to all the new changes and ultimately make the enhanced experience available to end users.
This process replaces the existing process that involves a wait-in period for manufacturers in receiving the new software release from chipmakers to modify the software specific to their hardware.
Google has added the Project Treble framework to Android Oreo to make the update process better on newer devices. Although it was initially reported to be a part of new hardware shipped with the latest Android version, Google announced the framework for its Pixel range and also started working with manufacturers to implement the new experience on a larger level. But it appears that OnePlus is not among those device makers who are bringing Project Treble to their existing devices.
Notably, the absence of Project Treble doesn't mean that OnePlus will not deliver new Android versions to its current range. The OnePlus 5T, which went on sale earlier this week with Android 7.1.1 Nougat, is confirmed to receive a stable Android Oreo update in early 2018. The company also recently started rolling out Android Oreo-based OxygenOS 5.0 OTA update for the OnePlus 3 and OnePlus 3T.
