There are many occasions where a plane under an AOC can and will file G, and apparently also the other way around is possible.
Yes, you are right Dirk...you could have a plane under an AOC flying private as G, (it happens a lot for instance when carrying corporate/owners, boss in private leisure, etc), however the opposite its not legal
afaik. If you dont have an AOC you cannot carry Commercial/Public air transport of pax and cargo.
(At least in Europe)
.