I have installed both Catalina and Xcode 11 from store and they are up to date:
Yesterday I have uploaded a new binary using fastlane. Today I got this message from Apple:
Dear Developer,
We identified one or more issues with a recent submission for App Store review for your app, "Gözen Security" 7.3.2 (67). Please correct the following issues, then upload again.
ITMS-90534: Invalid Toolchain - Your app was built with an unsupported version of Xcode or SDK. If you plan to submit this build to the App Store, make sure you are using the GM version of Xcode 10.1 and the SDK for iOS 12.1 and watchOS 5.1, Xcode 7.1 and the SDK for tvOS 9, or Xcode 6 and the SDK for macOS 10.9 or later. If you are using an Xcode beta version to test your app, make sure you are using the latest supported version. For more information about supported beta versions, view the App Store Connect What's New page (https://developer.apple.com/app-store-connect/whats-new/).
Best regards,
The App Store Team
Since Catalina and Xcode 11 are officially released why Apple still want me to use Xcode 10 and iOS 12?
Xcode was updated to 11.2.1 version. Builds made in Xcode ver 11.2 are not valid anymore. If you do not see the update in the Mac App Store then go to your developer account and download new Xcode manually.