Samsung Galaxy Tab S 10.5 getting Android 6.0.1 Marshmallow update at AT&T
Along with the announcement, AT&T also published a short changelog of the update, so if you have the Galaxy Tab S 10.5 from this particular U.S. carrier here are some of the new features that you'll get.
Aside from that, Samsung also included NumberSync functionality, which enables users to take advantage of their tablet to make and receive voice and video calls, using their existing phone numbers. The great thing about this functionality is that it works even if you don't have your smartphone with you.
Obviously, all the new features and improvements implemented in Android 6.0.1 Marshmallow will be added via upgrade as well. It's also worth mentioning that this download is quite large (around 1GB), so make sure you have plenty of storage on your tablet.
Although AT&T confirmed the update is available beginning October 13, you should manually check for it by heading to Settings / General tab / About device / Software update / Check for updates.
source: AT&T
Things that are NOT allowed: