Samsung is usually pretty good about getting the latest version of Android to their users on a pretty efficient schedule. It might not be as good as the Nexus series, which Google makes certain receives the new Android upgrade first, but lately a pattern is starting to emerge as far as when Android 6.0 (otherwise known as Android M or Marshmallow) is coming to Samsung devices. Here is the latest news on Android M Version 6.0 Marshmallow Release Date for Samsung Galaxy S6, S6 Edge+, Note 5, Note 4, Note Edge, and S5 on T-Mobile, Verizon, US Cellular, AT&T, and Sprint.
The news on Gotta Be Mobile is that Marshmallow is beginning to roll out in many places for the Galaxy S6 and the Galaxy S6 Edge. Updates have been rolling out in South Korea, the United Kingdom, the Netherlands, and other places in Europe. So it really is a matter of time before it works its way to Canada and Telus has confirmed an update for March 30. After that, it is on to America where all five major US Carriers (AT&T, Verizon, T-Mobile, Sprint, and US Cellular) should have it.
As for the Galaxy Note 5, this newer device is also getting its Marshmallow rollout, and it looks like it is going slowly as well. A separate report from Gotta Be Mobile states that the rollout is in Korea, but unlike the Galaxy S6 phones, the Note 5 has come to America, at least if you are a Verizon subscriber. This makes sense that it came to Verizon first, as it is common for some upgrades to come to certain carriers earlier, as Sprint and T-Mobile are working on their Marshmallow download.
Therefore, when the Android upgrade of Marshmallow does come to certain devices, it might not hit them all at once. For Samsung older devices, Tech Times reports that April could be the date for Galaxy Note 4 and Galaxy Note Edge users to receive their upgrade into Android M. Then in May, the Galaxy S5 and the Galaxy Tab S2 (the 8-inch and 9.7-inch models) will get their fair share of Marshmallow, followed by the Galaxy Alpha in June.
Users of such devices listed above should go to their "Settings" menu on the "System Update" section to see if the update is available Over The Air (OTA). If it is, then you should be able to download it and get it working on your Samsung device within minutes. If not, just wait a little while longer, but you'll have to wait forever if your Samsung device is too old.