How do we analyze the .ipa file after uploading it to TestFlight?

We are having trouble analyzing our app's size. When we evaluate the app size locally, it might show a decrease, but after uploading it to TestFlight, we sometimes see the exact opposite result. Evaluating this is very complex. We suspect this discrepancy is due to server-side optimizations by Apple, but there is a lack of clear documentation and articles explaining the process. Can anyone help clarify why this happens and how to measure it accurately?

How do we analyze the .ipa file after uploading it to TestFlight?
 
 
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