The latest update is not available through OTA, instead you'll have to manually install it if you want it. To update your unlocked Galaxy S7 Edge manually, you’ll need to download Samsung's Smart Switch onto your device and Windows/Mac computer. You grab the necessary files from Samsung's Website.
The update comes with latest new UX,various performance modes, new notification panel and other interesting features along with Android Nougat goodies.
Unfortunately, we don't have any information regarding the Android 7.0 Nougat update for the unlocked Samsung Galaxy S7 (non-edge). We’ll let you know, once the update is available.