The Battle of Britain Five Months That Changed History, May—October 1940 by James Holland (z-lib.org).epub

that day. The threat remained, however, because the essence of the split had
still not been resolved.
There was a third War Cabinet that day, at 10 p.m., but it had been
called to discuss yet another crisis. The Belgians had surrendered. As of
midnight that night, they would no longer be in the fight. The north flank of
the BEF was again desperately vulnerable and a mere 7,669 troops had been
lifted from Dunkirk this first day of the evacuation. Whether Churchill
could win over Halifax – and the rest of the War Cabinet – would have to
wait another day. The stakes could not have been higher.