All builds are now done using XCode 12.1.
Xcode 12.1 includes SDKs for iOS 14.1, iPadOS 14.1, tvOS 14, watchOS 7, and macOS Catalina 10.15.6. The Xcode 12.1 release supports on-device debugging for iOS 9 and later, tvOS 9 and later, and watchOS 2 and later. Xcode 12.1 requires an Intel-based Mac running macOS Catalina 10.15.4 or later.
https://developer.apple.com/documentation/xcode-release-notes/xcode-12_1-release-notes