Update Iphone 7 Plus

1. Here’s what you need to do to update your iPhone, iPad, or iPod touch to iOS 12. Create a backup Back up your iPhone, iPad, or iPod touch so you have a copy of your important information just in case you need it.
2. The iPhone 7 and 7 Plus will get iOS updates on till 2021 since the iPhone 6 is stopping on IOS 13 in 2019 the iPhone 6s will stop in 2020 on iOS 14 so yes it'll get updates until 2021 which is iOS 15.

1. Iphone 7 Plus Update Firmware

What's New in iOS 10.0.2:The update includes fixes for several minor bugs, including an annoying problem that was causing the Lightning headphone controls to be disabled after a period of inactivity.The glitch seemed to happen randomly and could only be fixed by unplugging and re-plugging them.

Iphone 7 Plus Update Firmware

IOS Updates - Apple® iPhone® 7 / 7 Plus. Connect the iPhone to the computer using the supplied USB cable. When tethered, iTunes opens automatically on the computer. In iTunes, select the iPhone under Devices in the left column. For iTunes version 11 or higher, select the iPhone button in the upper-right.