Franek, thank you for explaining why the Polish decoders spent the war in France and not in the UK, but I am still rather confused. You say they did valuable work, but for who? Vichy France, the French Resistance? Presumably it was not for the Free French, who were in London. It said somewhere (wiki?) that they initially and understandably went to France to be with the Polish Army who had gone there to continue the fight. That got promptly knocked on the head by the sudden collapse of France. Many of the fighting Poles got away to Britain to fight the Germans from there, but not the decoders. Why?
Had they already been given the cold shoulder by the Brits? It seems unbelievable if that were so, as Bletchley was beginning to break Enigma (especially the Luftwaffe codes), and it would be obvious that to leave the Polish codebreakers behind in France could seriously compromise any future use of Ultra. Was their fate less determined by the British than by the French, in particular Major Gustave Bertrand, their 'host'? Like I say, it doesn't quite add up. Well, not to me at least...