Ok, after looking all the sources stated here I am quite convinced that only 1 KV prototype operated in the Summa sector of Mannerheim line during the Winterwar. As said it was a prototype which suffered all sorts of problems, but due to hurrying it was desided by the Soviets to put it in mass production nearly as it was. Renaming to KV-1 model 1939 which has caused confucion as to when the tank was fullu available. So the model name (1939) is not for production start time but for first prototype appearance. Full production started sometime in late March 1940.
Also in March after the war was already over 2 KV prototypes (whit 152mm gun) were tested against already empty Mannerheim line forts. These tanks were a direct response to upgun the KV-1 to destroy forts. It was aproved after the test and further production started in 1940 whit the name of KV-2.
So the notion of KV-1 tank(s) in plural refers to all these three (3) KV tank prototypes of which only one piece (a KV-1 m1939 prototype) actualy saw some combat in the winterwar in the already mentioned Summa sector.
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Btw. just watched a documnetary on Discovery Channel about the KV-tanks. It showed footange from destroyed T-26 tanks in Winterwar saying it was from Spanish civil war. Gets better when there was a picture of Finland as it was after 1944 and it placed the Mannerheim line where the Salpa line is locaded about 100km off from its correct location!
Then the best part when tens of KV-1 tanks are said to have attacked in the village of Summa whit finnish troops destroying them all whit molotov cocktails. On the backgroud footage of KV-85 and JS-2 tanks attacking against Germans sometime in 1944 or 1945 is shown.
I would rate the document hopelesly inaccurate in its historical accuracy, but it did show that the myth of massed KV-1 tanks being used in winterwar is existing at least somewhere. It is not in any Finnish history books nor does it make any sence, so where the myth came is a complete mystery to me.