Inspection of tanks and crews before the war.

Polish tanks 1939

TP-7, 9 ton, classified as light, was (according to my source) the most modern Polish tank of that time.

Polish tank 1939

During the years 1941-1942, the First Polish Army was formed (organised, armed and trained) in the Soviet Union. All soldiers of the Army were ex-prisoners of war and ex-civilian prisoners. The Polish organisers managed to assembly 6 divisions, 2 independent regiments and 1 independent battalion. There were also some non-combat units, which covered the areas of training and organising. 
In 1942 Stalin withdraw his permit to go on with formation of Polish units, and in this same year, 41 thousand of Polish military personnel and 74 thousand of Polish civilian citizens left the Soviet Union. They were transported across the Caspian Sea, from Krasnovodsk to Pahlavi in Iran. They left to continue the fighting from the west, with their western ally.  
According to many historians it was a mistake. 
LS