This happened, as Soviet troops had advanced in the course of Operation Bagration in the summer of 1944 to the Vistula and to the frontier in East Prussia.
In addition, fortifications in Glogau, Breslau, Posen and Danzig as well as on the Hela peninsula and the Öxhöfter Kämpe near Gotenhafen were set up or repaired.
The expansion of the fortresses and ramparts was carried out by the mass deployment of volunteers and forced civilians and the Hitler Youth.
However, this armament was also deducted on the orders of Colonel General Alfred Jodl to the Western Front, so that only a few guns larger caliber could be installed in the eastern fortifications.
It remains to be noted that the fortifications made possible by the slowing of the Soviet advance many refugees, especially from Silesia, Pomerania, West and East Prussia.