[wool_gather]

There is a workaround if you use IAPs for the upgrade rather than pre-download purchase, although you have to release the new version as its own product, not as a simple version bump of the existing app. The newer version can check whether the older version is installed and offer different purchase options.

Apple introduced app bundles a few years ago, and those can now be used, with the same caveat of putting up the new version as its own app. In this case the App Store itself can do the check for the original version and change the price of the bundle.

It's certainly not ideal, but it is possible. Pythonista and GoodNotes are two that I know of that have used each of these workarounds.