Note 4 Settings->System->System Update missing?

[AC Question]

I've had Galaxy devices for years, but just noticed on my (2 month old) Note 4 that there's no System Update option under settings. What gives?

 

[B. Diddy]

Welcome to Android Central! It's usually in Settings>About Phone, although I know that Samsung's menus are often different.

Is the phone rooted? If so, is it running a custom ROM?