That is an opinion,for which there is no proof : the German policy against Poland was the same as the one against CZ : bluffing and threatening to force CZ/Poland to accept its demands and to scare Britain . Only ,ONLY,if the threats did not work (September 1938/August 1939 ) would force be used :the decision to use force, depending on the possibility on a deal with Stalin, was made in August 1939, NOT in March : nothing special happened in March .wm wrote: ↑13 Jan 2022 22:54
Actually, it could be found in many contemporary Polish diplomatic reports.
Andis one of the weaker ones.Germany, has lost its calculability, with which it was endowed even amidst difficult problems.
Polish diplomatic reports , diplomatic reports in general, do not give a correct report of the intentions/decisions of the opponent ,because, as all reports ,their contents are decided by what want their superiors : if the Foreign Office wants an alarmist report , they will have one .It is the same for the reports of the spy services : US secret services tell us that Russia will invade Ukraine,because Washington wants such messages .
Every one knew in March 1939 what Germany wanted , everyone knew this also in March 1933 and before .