I would usually agree with this approach. But there are not many good options in this case, as the next flight, six hours later is an OA flight ... So missing the connection would indeed, as mentioned by upgrader, involve a one day stay in Athens. And as both OA and A3 flights are economy only, there does not seem to be an option for purchasing a business class ticket and having it endorsed to OA in case of misconnect. Or I am missing something about domestic fares in Greece ?