Ok im a bit late but still better than never. ^^

Graviteam.ua:
75 % Discounts for ALL games APOS & ALL DLC (ENG & RUS)
Period discounts – from June 13 to July 13, 2014

That means all Graviteam games on GamersGate are at 75% discount till July 13.

Also on Steam Graviteam Tactics Operation Star, and Volkonovka DLC is also 1/4 of its normal price till the end of Steam Summer Sale on June 30.

So heres the plan:
1. Buy base game on Steam to show them CoD kiddies how leet grognard wargamer you are
2. Buy DLC from Gamersgate to get the full APOPSTAR experience
3. PROFIT!!!