Over the winter, German deception operations were conducted and indications of an offensive through Switzerland diverted French attention at the end of 1916. The British were occupied by reports of troops and heavy artillery moving into Flanders and increased numbers of agent reports of troop movements from Lille, Tourcoing and Courtrai. Until January 1917, the British took seriously a possible limited offensive towards the Channel ports and made Flanders the subject of most of their long-range reconnaissance flights. Rupprecht, the northern army group commander on the Western Front, was made responsible for planning the devastation of the infrastructure within the Noyon Salient and the retirement to new defensive positions along the (Hindenburg Line), codenamed the (Alberich Manoeuvre). The Germans prepared a timetable; infrastructure in the salient was to be destroyed and buildings demolished from