Things could have probably been different if OnePlus would have said these two smartphones will stay on Android Marshmallow in the first place. With the company releasing the OnePlus 5 recently, it has led many to wonder how software will be supported on the OnePlus 3 and OnePlus 3T going forward. After the OP3/3T have been updated to Android O, we'll start moving the Open Beta Program from OP3/3T to OP5.
While Android O will be the last major OS update for the OP3/3T, Oliver does promise that the devices will continue to receive updates for the "foreseeable future". As OnePlus 3 and OnPlus 3T owners were in the dilemma whether their handset would get any software update in the future. There's now no word as to when Android O will be released for the 3/3T, but with Google expected to release public builds before the month is over, we'd hope that OnePlus can push it out before 2017 is over.
This is good news for OnePlus 5 users who wish to experiment with the latest Android features before they are released to the public. The company has not revealed the timeline for pushing Android O update for both the devices, but we can expect it to be rolled out before the end of 2017. Another question from different forum member asks why the Open Beta for the OP3/3T has more features than the stable branch.
Oliver also added that the August security patches for the OnePlus 3 and 3T will to be released "soon" while the OxygenOS 4.5 build will be out "in the next 1-2 months". The OnePlus 3 is just about 14 months old at this point, and the 3T is even younger at just 9 months.