I would like to know what the earliest deployment target I can use if I use the structured concurrency syntax in my app.

Debug builds work correctly when I run from Xcode. Release builds fail to load on iOS 10 and iOS 12 (probably 11 too, but I don't have one to test). Release build can be installed fine on iOS 13 and iOS 14. I am currently building with Xcode 11.2.1 It is not an issue with the deployment target. It is some kind of signing related issue which I don't understand. It is happening with multiple devices from multiple machines. dispatchsourcereadsocketblockinvoke:312: Failed to install application at file:///var/mobile/Media/PublicStaging/xxxxx-Release.ipa/ : Error Domain=MIInstallerErrorDomain Code=13 "Failed to verify code signature of /private/var/installd/Library/Caches/com.apple.mobile.installd.staging/temp.Jw6NIj/extracted/Payload/xxxxx.app : 0xe800800d (There was an error communicating with your device.)" UserInfo={LibMISErrorNumber=-402620403, LegacyErrorString=ApplicationVerificationFailed, FunctionName=+[MICodeSigningVerifier validateSignatureAndCopyInfoForURL:withOptions:error:], NSLocalizedDescription=Failed to verify code signature of /private/var/installd/Library/Caches/com.apple.mobile.installd.staging/temp.Jw6NIj/extracted/Payload/xxxxx.app : 0xe800800d (There was an error communicating with your device.), SourceFileLine=147}

How can I get a list of attachments from an EKEvent?