 On 11 August 1918, Posen, Westfalen, Kaiser, and Kaiserin sortied from Wilhelmshaven to support torpedo boats on patrol off Terschelling. On 2 October, Posen moved out into the outer roadsteads of the Jade to provide cover for the returning U-boats of the Flanders Flotilla. Posen was to have taken part in the last fleet operation of the war, planned for 30 October. The operation was intended to inflict as much damage as possible on the British navy, in order to retain a better bargaining position for Germany, whatever the cost to the fleet. War-weary sailors mutinied, which led to the operation being canceled. In an attempt to suppress the spread of mutinous sentiments, Admiral Hipper ordered the fleet dispersed. Posen and the other ships of the I Battle Squadron were sent out into the roadstead on 3 November, then returned to Wilhelmshaven on 6 November.
