It showed out, that the Finns had only about a dozen Vickers tanks available at the beginning of the war. But a lot of T-26s were captured and later incorporated in the armored battalion. Even in 1944 these were fighting.
That means, sadly the developers paid not enough attention to make it historical enough.
Sure, without tanks, the game would be not so fun, but if we "expand" the known facts, the situation can fun and still historical. Although, the T-26's have not yet fought in Winter War, but that is not so far from reality, so, with "expanding" the historical, they can be used already. So, the changes should be: you get the tank unit in the 2nd mission, but instead of captured T-26's, we get as reinforcements, the Vickers tanks. (I anyway do not like to capture something and already, in hours, these captured armor is battle ready, with trained crews... 
- arty, or guns are a different type, there is much more realistic to use captured equipment right on the battlefield. I guess. 
) And in mission 6, we get the captured T-26's instead of the Vickers.
Oh, and the rule for captured equipment, which can be replaced only 1/turn can be also applied to these types, because Vickers were rare, while the T-26 were captured in larger quantities.
I will look in the editor, to see, if it can be changed. Who already beyond mission 2 - as me too -, a solution can be to change the name and icon of both tanks. As they were technically anyway very identical, the stats will make no big difference (if any).
It is sad, the the devs did not pay attention overall to the historical accuracy: with the units availability, units in the scns, unit stats.
It would have took exactly just 2-4 workdays for one man research the facts and stats on the internet and incorporate it correct in the game. It's the same, as with the PzC's vanilla DLC's, where only the theater and region was right, almost every else was far from historic.
