In addition to resolving several known issues and adding support for the latest releases of iOS, iPad OS, TVOS and Mac OS Catalina, Xcode includes a few changes that reflect recent changes to Apple iPhone line-up.
On April 15, 2020, Apple released the second generation iPhone SE and discontinued the iPhone 8 and iPhone 8 Plus.
If you use Storyboard to create your app layouts, you may have noticed that the iPhone 8 has been removed from the list of devices in the “View as:” menu in Storyboard whereas the 8 Plus is still available. The new iPhone SE (Gen 2) has the same screen size (4.7”) and aspect ratio as the iPhone 8, so if you need to view your layout on an 8, you can use the SE gen 2 option.
The iPhone 8 Plus is still available, presumably because it and it’s predecessors (the 7 Plus, etc.) have a 5.5 inch screen, unlike the newer iPhone 11 series.