Sudden, artificial app size increase on App Store Connect - change in processing logic?

Hello everyone,

We recently noticed a sudden and unexplained increase in our app's download and install sizes on App Store Connect. The jump happened literally overnight between April 2 and April 3.

After auditing our commit history and running some isolation tests, it appears this increase is artificial and related to a change in App Store Connect's post-processing or size attribution logic, rather than our actual codebase.

The initial observation:

  • Build A (April 2): Download: 174 MB | Install: 380 MB
  • Build B (April 3): Download: 179 MB | Install: 386 MB

To figure out what caused the ~5 MB download and ~6 MB install jump, we looked at the diff between the two builds. We ran a local size analysis on the IPAs for both commits and the diff was just 18,287 bytes. Such a difference in the compiled binary absolutely does not account for a 5-6 MB jump in the final App Store Connect estimates.

To completely rule out our code, we took the exact source tree from Build A (which originally processed at 174 MB / 380 MB) and pushed a fresh upload to App Store Connect. Re-uploaded Build A increased in size to 179 MB / 386 MB.

Since re-uploading the exact same commit now results in the larger size estimates, it seems the discrepancy is not originating from our code.

Has anyone else experienced a similar bump in their app sizes recently? Could an Apple engineer provide any insight into what might be causing this?

To give a full picture of the situation - this increase is evident across all device models, but the figures quoted in the posts refer specifically to the iPhone 13 Pro Max.

Sudden, artificial app size increase on App Store Connect - change in processing logic?
 
 
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