We know that Samsung is working on bringing Marshmallow to its flagship collection, including the Galaxy Note 5. The timeframe of the update rollout is less clear, though if the experience of one T-Mobile user is any indication, Samsung has already made substantial progress.
XDA-developers forums user Danon Brown reports that his Note 5 (SM-N920T) received an update to Marshmallow by accident. Danon was playing with his phone’s software and ran into a problem regarding the IMEI code. He used Samsung’s Odin software to revert his device to the stock firmware and then he checked for updates. Instead of the most recent official firmware for his device, the phone updated to build.number MRA58K.N920TUVU2DOK5.
Danon has several screenshots as proof that his device has indeed received a major update.
It’s important to note that we could be looking at a prank here, and, even if it’s legit, this build is likely not-final, so nothing is set in stone for now.
Also, the visual changes could be due to a theme being applied, though one of the screenshots shows that only the default theme was installed on the phone at the moment.
The most visible functionality change is the new permissions system – apps like Gmail or Hangouts now request access to specific capabilities when first ran.
Unfortunately, Danon Brown didn’t provide more details about the build, but he said he would try to extract a system dump from his device. In any case, we’ll keep an eye on the thread and update you if info that is more substantial leaks out.