I am preparing a new release of my app to support iOS 13 Dark Mode and other enhancements.
I am using Xcode 11 beta 6 to archive with the intention of distributing the apps vis Testflight. However, the Archive fails with ERROR ITMS-90534 "Invalid Toolchain... unsupported version of Xcode of SDK... If you are using an Xcode beta version make sure you are using the latest support version..."
I downloaded Xcode_11_Beta_7 and unzipped to install. However, when I start beta 7 and display About, I see Version 11.0 beta 6 (11M392r). What could be the issue?
Generally speaking, what is the best strategy for working with beta testers considering most of them won't have iOS 13?