 Throughout this period, the battleships rotated through Malta or Toulon for periodic maintenance; Corfu became the primary naval base in the area.The patrols continued through late December, when an Austro-Hungarian U-boat torpedoed "Jean Bart", leading to the decision by the French naval command to withdraw the main battle fleet from direct operations in the Adriatic.For the rest of the month, the fleet remained at Navarino Bay.