sentences:  This operation was to thoroughly block the channel, and—coupled with the blockage at Zeebrugge (which the British authorities believed to be fully closed)—was to prevent use of Bruges by German raiding craft for months to come.All preparations for the operation were completed by the first week of May and on 9 May the weather was nearly perfect for the attack.The British armada had collected at Dunkirk in Allied-held France and departed port shortly after dark.