Hy,
I have uploaded the app to App Store with both architecture. Please see the attached image for Build Settings of TARGETS in Archi
Build Settings
TARGETS
Archi
Get the .IPA file which you had uploaded and Change the extension to .Zip and Unzip the file
And open the terminal and execute the below command, file ~/SOME_PATH/Payload/.app/
you'll get the architecture details for the IPA