Sorry if anyone misunderstood my comment. "To be covered by UK insurance you must be in the county the vehicle is in".  This does not apply to the country the car is registered and insured in.

If your vehicle is registered and insured in the UK you can leave it at any UK airport and go abroad and it will be covered.

If your vehicle is registered and insured in the UK and you leave it at the airport or anywhere else in another country (eg Spain - on your own land or the airport) and fly back to the UK or go on holiday to another country then you are not with your vehicle and it is not covered.