Motorola today rolls out the android nougat update to it's Moto X Pure Edition smartphone which was launched couple of years back in 2015. The update is currently live in US and is rolling out over-the-air to units in the country
As it's an OTA update will take time to reach every unit so be patient. Meanwhile you can head over to setting's menu and manually check whether the update is ready for your device or not.
Settings > About phone > System updates