On Saturday 25th May 1940, the Luftwaffe focused their attention on Allied pockets holding out at Calais, Lille, and Amiens. They did not attack Dunkirk.
Calais was held by the BEF (British Expeditionary Force) and surrendered on Sunday 26th May.
On that same Sunday 26th May 1940, at 15:30, Hitler ordered the Panzer groups to continue their advance, but most units took another 16 hours to attack. The delay gave the Allies time to prepare defenses vital for the evacuation and prevented the Germans from stopping the Allied retreat from Lille. The Halt Order has been the subject of much discussion by historians, many of whom considered the failure to order a timely assault on Dunkirk to be one of the major German mistakes on the Western Front. Another called it “one of the great turning points of the war”, and a third described it as “one of Hitler’s most critical mistakes”. Hitler himself believed that once Britain’s troops left Europe, they would never return. The retreat itself was undertaken amid chaotic conditions, with abandoned vehicles blocking the roads and a flood of refugees heading in the opposite direction.
Due to wartime censorship and the desire to keep up British morale, the full extent of the unfolding disaster at Dunkirk was not initially publicized. A special service attended by King George VI was held in Westminster Abbey on Sunday 26th May, which was declared a national day of prayer. The Archbishop of Canterbury led prayers “for our soldiers in dire peril in France”. Similar prayers were offered in synagogues and churches throughout the UK that day, confirming to the public their suspicion of the desperate plight of the troops.
It was just before 7 pm on Sunday 26th May that Winston Churchill ordered Operation Dynamo – the Dunkirk evacuation code-named also known as the Miracle of Dunkirk – to begin. Initial plans called for the recovery of 45,000 men from the BEF within two days, at which time German troops were expected to block further evacuation. As it turned out only 25,000 men escaped during this period, including 7,669 on the first day.