from our National Archive:
'The Polish Air Force
A small number of personnel from the Polish Air Force escaped from Poland when the Germans invaded. Polish squadrons were formed within the Royal Air Force. An agreement was reached with the Polish Government-in-exile in 1942, which formalised this arrangement. Documents detailing the arrangements will be found in AIR 20, AIR 19 and AIR 8.
It was not until late in 1944 that a Polish Air Force headquarters organisation was established in Great Britain in anticipation of the return to Poland after the cessation of hostilities. After the establishment of this headquarters the command of the Polish squadrons remained with the RAF. Operations Record Books (ORBs) of these squadrons can be found in AIR 27; the squadron numbers are as follows, 300 - 309, 315 - 318 and 663. '