Can't see how EasyJet Europe is a British company. (EasyJet originally was a British until Brexit fears gave them other ideas.) Prior to Covid-19 pretty well all flights from UK bases were operated by UK registered aircraft, not Austrian. Seems a distinction between EZY and EJU. The EasyJet website distinguished between the two e.g. "Your flight is being operated by Easy Jet Europe." (Sorry this is on the Virgin page but it's responding to an idea raised.)