There is no fixed standard at the moment.
The FAA has its Airship Design Criteria (P-8110-2) plus Advisory Circular 21-17.
EASA has a draft CS-30.
There is an old German-Dutch effort called Transport Airship Requirements.
None really address a hybrid air vehicle.
Best guess at the moment is that when TC comes, it is likely to be based on a mixture of the above plus special conditions.
AOC is something I know nothing about, sorry. My expertise is certification of flying machines not their operators.