Committing a configuration which does not list an offload option turns that option off, and removing the interface afterwards does not put it back.
The activation script only records an option while the adapter still has it enabled, so whether a testcase found one depended on which testcases had run before it - the state ratchets down as the suite progresses, and which testcases fail changes with the order.

Read the state the adapters booted with once and put it back before every testcase. Options the driver has pinned are left alone.