September 1944, German field post letter from Pioner-Bataillon 1536, 536. Volks-Grenadier-Division

German unit, sent likely form Estonia in September before retreating to Courland in Latvia. A week later Tallinn was already captured by Red Army.

https://www.lexikon-der-wehrmacht.de/Gliederungen/PionierBat/PiBat1563-R.htm