OnePlus has been hounded pretty regularly in recent months by anxious OP2 owners wondering when Marshmallow is coming. Well, there's an OTA starting to roll out today and... it's not Marshmallow. Still Android 5.1, sorry. It does, however, bring RAW support to the camera, new security patches, and other little fixes.
Here's the changelog from OnePlus.
- RAW support in OnePlus Camera
- Bluetooth compatibility improvement
- Ultra SIM compatibility improvement
- GMS 3.0 upgrade
- Improvement for roaming issues
- Fix for occasional image corruption issue in OnePlus Camera
- Security patch update
- Romanian language support
This is the first patch for the OnePlus 2 since the holiday season, so the comments on the OP forums are pretty solidly in the "where the heck is Marshmallow?" camp. There's no word when that will happen, but in the meantime, this isn't a bad update. The RAW camera support will be appreciated, and it's nice to see OP keeping up with security patches.
It's a staged rollout, so you probably won't be able to pull it right away. Give it a few days and it should be available to everyone.
Source: OnePlus Forums