Agreed....
I'm sure that there will be some Flight Crews who will be messed around.
Equally, there will be quite a few who will finally get the base the've been waiting for since forever - whether UK nationals currently stuck in the EU, or EU crews currently stuck in the UK - as crews are transferred around the network between the two operating units. It's amazing how Management can accomplish these transfers at times of crisis but can't do it at times of non-crisis.
The other option, of course, is for EZ service in the UK to be operated by ACMI arrangement with EZ aircraft from the EU based legal entity ( or the other way round, of course ) as schedules require. Absolutely certain that the UK would not object to this - the EU might need persuading.