OxygenOS 9.0.2 comes to the OnePlus 3 and 3T with the April 2019 security patch from Google, a brand-new user interface, Google Duo support in the Dialer, a new gaming mode (3.0, with notification for third party calls and displaying the text content of the heads-up notifications), Google Lens support, as well as various bug fixes and tweaks.
https://www.notebookcheck.net/Android-Pie-based-OxygenOS-9-0-2-coming-to-the-OnePlus-3-and-3T.421470.0.html
I haven't Recieved my Update yet (3-6-19), I even tried doing it via offline package (zip / ROM) but still I wasn't able to update it properly, It failed several times.