Oneplus 3 and OnePlus 3T are now receiving new updates under OpenBeta Channel. The latest OxygenOS Open Beta 38 for the former and Open Beta 29 for the latter, notably, board the latest SMR dated, 1st June 2018. The official changelog of the updates for both of them goes as follows:
System
OnePlus Switch
Apart from the latest security patch, the updates do cater some general bug fixes and improved data transfer stability as per the changelog. Users, those who have installed the latest beta are happy with the build as they haven’t encountered any sort of major bugs so far. Moreover, most of the folks over at OnePlus forum have a notion that this might be a final beta prior to the OxygenOS based on Android Oreo 8.1 update for the devices. However, that may or may not be the case as there is no official word regarding when the Android Oreo 8.1 beta testing will begin for the OnePlus 3 and its tacked up edition.
That said, OnePlus 3/3T users currently on beta builds should have, by this time, received an update notification to install the update. If not, either you can wait for some more time for the update notification to pop-up on your device or manually download and flash the OTA zip.
OxygenOS OpenBeta 38 for OnePlus 3
OxygenOS OpenBeta 29 for OnePlus 3T