[3] Thanks to Hollard's reports and information from his agents, the V1 launch sites in France were systematically bombed by the Royal Air Force between mid-December 1943 and March-end 1944.

In his book Crusade in Europe General Eisenhower wrote that had the Germans been able to develop their weapons six months earlier and to target Britain's south coast, Operation Overlord would have been near impossible, or not at all possible.

He later resigned from his post when his company began working for the occupation authorities and gained employment with a manufacturer of wood gas generators, which enabled him to travel around France using his job as a cover.

In 1941 Hollard crossed the defenses barring access to the French Free Zone and the Swiss border for the first time to offer his services as a spy to the British embassy in Bern.

Count Folke Bernadotte, who was vice-president of the Swedish Red Cross, had been informed by the British Intelligence Service that Hollard was there, but was unable to locate him, so pleaded that "all French-speaking prisoners be transferred to another ship", the Magdalena.