There are references in Die Vertreibung der deutschen Bevölkerung aus den Gebieten östlich der Oder-Neiße to the relocation to the former German territories of residents of destroyed Warsaw and  the employment of German forced labor in the clearing operations in post war Warsaw   :::Also the Polish census data from 1950 indicates that 480,000 former residents of pre war Warsaw city and Warsaw province were resident in the Recovered Territories in Dec 1950.   :::The refugees of destroyed Warsaw needed a place to stay and somebody had to clean up the mess and rebuild the city   :::One cannot now deny that the Expulsions and the destruction of Warsaw are related     