I recently returned to some Swift 3 projects on a 2011 Mac Mini. I updated it to High Sierra 10.13 but it was still too old to download the latest Xcode's to update my swift projects. I waited for the Mini to get a refresh, and finally came the M1 and I bought one! I installed the latest Xcode (12.5.1) on my lovely M1 Mini and when I open my Swift projects I am told "Unsupported Swift Version", "This version of Xcode does not support building or migrating Swift 3.x targets" and "Use Xcode 10.1 to migrate the code to Swift 4" Fair enough. So I downloaded Xcode 10.1 from the "more" link in the download page (https://developer.apple.com/download/all/). I expanded the xip. But when I run this Xcode, it won't start. I am told "In order to use Xcode, you need to update to the latest version. The version of Xcode installed on this Mac is not compatible with macOS Big Sur. Download the latest version for free from the App Store." So now what can I do? Please help! Thank you!