🇬🇧️ - The BBC has a program called "Black Skies" which provides for the establishment of an emergency radio studio with about 100 employees to broadcast government messages in the event (ie, when) of major disruptions to critical infrastructure.
This program specifically provides for a complete shutdown of the Internet, and the studio will broadcast government messages via FM communications and satellite channels through secure systems that are not connected to the Internet, with sufficient supplies to operate for at least three days.