Revert "Remove 2.0->3.5 entirely"

This reverts commit dd97e3ff3f95338ddb4aff28f0b8a9276c0ae0e9.
Revert "Don't expect AOT caches in 2.0/ anymore"

This reverts commit be2de19da4ec9a377c8e2e2e197c3ee55e7500d8.