the second map leaked yesterday was called "Studyanka" and was rumored to be Polish. A quick background check revealed an interesting truth: the map is actually indeed historical (at least the name is), as it is based on the battle of Studzianki. The map is actually connected to the T-34/85 "Rudy" historically, as the battle was covered by the "Four tankmen and a dog" TV series.
The actual battle happened in August 1944 during the operations in Poland, where Polish forces with their Soviet allies were attacking the Germans around the Vistula river. The battle was fierce with both sides losing over a thousand men and several dozen tanks and it resulted in Polish and Soviet victory.