Motorola started rolling out the Moto G4 Plus update to Android 7.0 Nougat about three months ago, but strange enough, it is only now that the same update has started rolling out to the unlocked variant of the phone in the U.S.
The Nougat treat is headed to the Moto G4 Plus as an over the air update and as such, it will take time before you probably get it on your phone. The update is coming in with build number NPJ25.93-14 and it finally bids goodbye to the Marshmallow OS that debuted with the device about a year ago. All the perks that accompany the new Nougat OS, including the Doze mode, multi-window mode, and new notification features.
As noted above, OTA updates take time before hitting all affected devices and as such, Moto G4 Plus users can also take a shorter path to receive the OS by going to Settings>About phone>System updates>Check for updates manually. This should give you an early access ticket to the rolling out Android 7.0 Nougat OS rather than wait for the OTA notification, which could see you wait until next week.
Given that Android 7.0 Nougat first hit the unlocked Moto G4 Plus some months ago, it is possible that the wait for the newer Android 7.1.1 Nougat could go well into the second half of this year, unless otherwise. So far, the Lenovo-owned company has started testing the latter OS on the G4 Plus but the expected release date is still unknown.