I uploaded a build before one week from xcode 9, it didn't have any problem and was successfully uploaded to the testflight. But I upgraded to Xcode 10 , and now when I upload build then it starts complaining as:
ERROR ITMS-90725: "SDK Version Issue. This app was built with the iOS
'${appSDKVersion}' SDK. All iOS apps submitted to the App Store must be built
with the iOS '11.0' SDK or later, included in Xcode [9.0] or later. Please
update Xcode and rebuild your app."