 Complete the following phrase:  The Battle of France had already begun when 37 SL Regiment began embarking. Regimental HQ and a composite battery comprising one troop from each battery embarked at Dover on 15 May 1940 and landed at Dunkirk the next day. They were followed by 307 Battery, but the rest of the regiment was halted on the road to Dover and returned to Aldershot. The Composite Battery and 307 Battery eventually joined RHQ, driving through streams of refugees, but because of the rapid advance of the Germans, they were withdrawn to take up positions protecting Le Havre 307 Bty with 24 lights and Harfleur Composite Bty with 13 lights, under 3 AA Bde while the main BEF was being 