Here's how you can set the time for which Always-on Mode remains active on your Galaxy S7/S7 Edge
Samsung has started rolling out an app update for the Galaxy S7, S7 Edge which updates the Always-on Display mode with a configurable time-frame when it remains active.
Always-on Display was introduced with the Galaxy S7 and Galaxy S7 Edge but its not as feature rich as Motorola's offering on its smartphones. But Samsung is working to add new features to make it more functional. With the new update you can set the time during which always on mode would work. Once you have updated the app you will a similar screen as you see below when you go in Always On Display settings. You can now choose the time during which you want the mode to be active. One more thing, if you are using the Galaxy S7 Edge, then the night clock settings will take precedence over always on display.
So, you can have it on for when you are working to keep a track on notifications and off at night to save some battery. At present the Always-on Display functionality is still quite basic with no way to interact with notifications, but its good to see Samsung add some usability features and working on the mode more.
If you haven't updated yet, just head over to Settings -> Display -> Always On Display -> About Always On Display and install the update.