HE 111Z winter camouflage?

I am building the Hasegawa Heinkell HE-111Z, the famous German hybrid of two Heinkels joined into one as a glider pull.  The box cover shows the plane in what seems to be a patchy white/gray winter scheme and the instructions give alternatives for the usual RLM dark green/black green.light blue camouflage used in photos I've seen of the Z's--only 12 of which were produced.  The instructions also have a page for winter camouflage, which indicates the modeler spray flat white (deliberately sloppily, I assume) over the dark and black greens pattern.  This makes senses in the way such camouflage was quickly added to adapt to particular conditions, with white paint slopped on by hand,  but I can't find any archival evidence that any of  HE-111Zs ever used winter camouflage.  There is some conflicting histories saying the Z was intended for action in Russia but did not serve.

Anyone know anything definitive? I;d like to take a crack at the winter camouflage--if it existed for the Z!