A new leak supplied via Twitter alleges that OnePlus will reveal its early-2020 flagship phones in about a month from today (March 14, 2020). An avid follower of this OEM's rumors might have noticed that 1 putative variant has been left out of this headline; another tipster now believes it will get its own launch date for later on in the year now.
https://www.notebookcheck.net/The-OnePlus-8-and-8-Pro-are-now-tipped-to-launch-in-mid-April-2020.457517.0.html