The Worek Plan was put into action with the German invasion of Poland, after a distress call was received from the garrison at Westerplatte on the morning 1 September 1939. Several hours after hostilities started, the submarines received communications by radio to open the envelopes containing orders to implement the Worek Plan. "Wilk" loaded 10 torpedoes, 22 mines, and 114 100mm shells (for the deck gun) before departure. Due to heavy air activity, the submarines had to approach their positions submerged. "Orzel" was ordered to attack the "Schleswig-Holstein", should the pre-dreadnought leave Danzig. By the evening of the same day the last submarine ("Sęp") arrived in its sector.