Just a thought – CampingGas have a larger cylinder which is available in Italy. It is a 909 and 5.7Kg. We have had no problem getting it refilled in Montenegro and Croatia. It has the same circumference as their other cylinders but is obviously taller. It might be worth putting pressure on them to provide this cylinder in the UK now that Calor has become doubtful in the long term. Maybe one for you, Bob!
The membership association for owners of Dufour Yachts