Correct, that is a late 1944 action and the Czechs never produced the stamped trigger guards during the war, that is a subcontracted piece used in their production. The “winter trigger guards” are actually a different profile than that one, this one simply has damage altering the shape. The so called winter guards were designed by the Germans but never produced beyond prototypes during the war. After the war and the subsequent complete usage of left over wartime parts they began production of this simplified winter guard for their rifles.

Beautiful rifles by the way, I have yet to find a wartime one! The reason for the initial postwar lack of the guide rib is undoubtedly a utilization of 1945 production bolts in which the guide rib was omitted from the bolt as a production simplification.