OnePlus 2: connectionproproblems will be fixed with an update
of Martin Schneider 
on January 02, 2017, 16:45 pm | Write a comment
The OnePlus 2 connectionproProblems with the mobile network are to be resolved with an update from OnePlus. The successors have not had any problems with the connection so far, so the OnePlus 3 and 3T will not receive an update.
The Chinese company announced in official forum indicated that the update would be on its way to the owners. It would take a few days before everyone could install the update. OnePlus is known to be quick when it comes to updates and general software updates, which is why the whole thing should not take longer than two weeks. But that's just a guess!
Oxygen OS 3.5.6 is a reinforcement patch
The update version called 3.5.6 only patches the problem with the connectionproproblems, but the problem with the IMEI number or the Google security updates still remains. The IMEI number is no longer accessible, but this could help support. OnePlus itself is aware of this problem and says that it is taking care of it.