The update being rolled out has software version J727T1UVU3BRH3 and not only installs Oreo 8.1 OS, but also a new security patch for the month of June 2018. Why Samsung would release an Oreo update in mid-September with a June patch still amazes us, but at least there’s a new OS to counter this shortcoming.
Like any other software update, the BRH3 update is coming in over the air, meaning not all Galaxy J7 Pop units on MetroPCS will get the OTA download notification at the same time. The wait might take several days, but you can try jumping ahead of the queue by heading to your Settings > About phone > Software update and check for updates manually.
This is a major OS upgrade, which means the update size is huge. Before downloading the update, make sure you have access to stable Wi-Fi connection and your battery is at least 50% full.
Related: Samsung Android 9 device list
Note that T-Mobile has a variant of the J7 Pop with model number SM-J727T, but there is still no sign of Oreo update for this model. Of course, it won’t be long before the update shows up not only on this variant but also on other carriers.