Looking for some advise if anyone has experience with diving around Gallipoli.

I'm heading over with a group at the end of September to dive wrecks in the Gallinpoli area. We were informed by the dive operator this week that max depth for standard dives is 30 meters and under some circumstances to 42 meters. We are all hypoxic trimix divers regularly diving deep wrecks and had shortlisted several historic WWI wrecks we were planing to dive on the trip. But the dive operator this week is now stating we are not able to dive any deep wrecks. They reference the local "Open Circuit" standards which do appear to be strictly enforced in Turkey from what I can read. Most of our group are OC but there will be a few of us on CCR.

I'm looking for someone to explain to me the regulations and what can be done to organised access (permits?) to the deeper wrecks and if anyone has local contacts that might be able to assist with access. Any advice would be greatly appreciated.