This slate that made its debut loaded with Lollipop has just received its WiFi certification running Android 7.0, which is certainly the last major OS upgrade it will get via the official channels.
https://www.notebookcheck.net/Samsung-Galaxy-Tab-A-9-7-spotted-with-Android-Nougat-on-board.237666.0.html
Confirmed. My new Galaxy Tab A was delivered with Nougat in September and it runs fine.