The best estimate I have found from open sources in the English language are from an English language edition of
Russia Beyond the Headlines online publication found here.
In the article, T-14 Armata production is reported as follows: "The Armata will go into mass production in 2017-2018 and Russia’s armed forces will receive 2,300 T-14 tanks by 2020." It may not be much of a stretch to extrapolate that T-15 production would mirror that of the T-14 as they share common chassis, hull, and power plant.
I doubt Russia would put a handful of T-14/T-15's into a foray into Estonia, so if she has them, I do not think they are in sufficient quantities to warrant putting them in the game. However, it would be interesting to do so, as I understand the T-15's are to keep pace with the T-14 so as to provide infantry support where needed; thereby, making for an interesting scenario. Alternately, I imagine T-15's riding shot gun with the current front line T-90, if Russia had the quantity, but certainly we could put a few in the game.
The National Interest is running with this headline: "Russia's T-15 Armata: Moscow's Fighting Vehicle of the Future?" So, we may infer, it is projected, at least by the National Interest staff, the vehicle is not "ready for prime time." It ain't Deion Sanders just yet.
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