I'm not sure the A330-300 can use Cork anyway. The A330-200 should be OK.
But, realistically, Aer Lingus are not going to operate long-haul out of Cork
Why?
- Wrong aircraft types (A330 too large, A320 lacks the range)
- Fully utilised A330 fleet
- Maintenance issues from a single A330 based in Cork
- Dilution of existing market from Shannon and Dublin
- Almost everyone not going from Shannon or Dublin leaves on an EI flight to LHR or AMS
The only reason they might set up a service from Cork is to reclaim their territory if another operator came in.
In the meantime, if it ever does happen, it's likely to be a US operator of 757, 767 or 737-900s.