My app is built by AppStudio/VoltBuilder using the current version of AppStudio.
I just tried to upload to Amazon and got this message:
Failed to upload APK. An App file with higher minSDK version must have a higher version code.
The APK you just uploaded with version code: 1998 and minSDK version: 24, conflicts with an existing App file with version code: 20800 and minSDK version: 22.