Flak Railways Units were from February 1945 subordinated to 30. Flak Division. There are known several snapshots of AAA-Train during Prague Uprising. Usually, as wrote Ed West, on railway car platforms were mounted circle concerte structure with 20 cm Flak-Vierling Guns. Three such concerte structure survived WW2 and are exhibited by Vojenské Muzeum Králíky (Military Museum Králíky). See:
www.armyfort.com/cz/fotovideo.php?id=149&view=1