At time of open beta release there are four factions to choose which according to the developer will increase to nine. (lifewire.com)
The company's core development team was on holiday at this point last year due to the Chinese New Year, consequently pausing open beta releases for the OnePlus 3 and OnePlus 3T for a month, but no such announcements have been made this year and the firm will presumably continue issuing software updates for its devices on a monthly basis. (androidheadlines.com)
OxygenOS being extremely minimal in terms of modifications to Android, people are hopeful that we can see the first Open Beta release by the end of September, though there have been no guarantees. (xda-developers.com)