Could it be that they mean
they require F/O's for their performance A A/C?
Since naturally there's performance class A, B, C,. (Where C is old a/c's, right?)
Performance Class A: Multi-engine a/c powered by:
> Turbopropeller engines with a max. approved passenger seating configuration of more than 9 or a maximum take-off mass exceeding 5700 kg,
>AND ALL multi engine turbojet powered aeroplanes.
What this means is that all multi engine TURBOJETS are class A. At least from what I understand in my notes.
Anyway I believe this is what they are after because it does make sense to quote a performance class rather than saying the whole bubble babble.
Cheers