Today I had to send an update of my iOS audio-plugin (standalone + AUv3 appex) and noticed the archived product don’t appear in the “iOS Apps” category in the Organizer, thus meaning you can’t submit it to the App Store.
This seems to be related to the new build system introduced with Xcode 10. Fortunately, the legacy build system is still available: go to
File > Project Settings... and select it from here. This did the trick.
Hope that may help.