Prior to the release of its 2018 flagship, OnePlus had publicly committed to bringing Pie to its 2016 and 2017 phones. This week, the company partially delivered on this promise, releasing a new beta of its OyxgenOS software based on the newest version of Android for the 5 and 5T. The beta also includes the new OnePlus UI for Pie.
https://www.notebookcheck.net/OnePlus-5-and-5T-get-official-Android-Pie-based-beta.377861.0.html