InertialLemon

Bitcode alone might not be infinitely malleable. But given that Apple knows intimately the original platform the submitted app targeted, it has the ability to add additional logic in iTunes Connect that permits tweaks and assumptions you couldn't get away with in the promiscuous and agnostic setting of a generic compiler toolchain.

Every single binary every emitted by LLVM has been Bitcode during the compilation process. The only new element here is that Apple's asking for this intermediate product in order to be on the App Store.