OnePlus' chief executive, Pete Lau, posted a tweet with more details on a "new device", as promised. It mainly consisted of what could be a new tagline for 2019, in addition to a short video showing a device that could have curved sides and nothing along its top edge. This, then, may be the rumored 7 Pro.
https://www.notebookcheck.net/OnePlus-CEO-s-tweet-appears-to-confirm-some-rumors-about-OEM-s-next-flagship.418192.0.html