What will happen if multiple purchases of the same DLC(s) have been done through different payment methods?

It seems that you can multiple purchases (like two times) DLC(s) via Gaijin and Steam (one same DLC purchased from both method). Will you get doubled benefit such as doubled amount of GS and doubled time of Licence? Or you will just get nothing for the second time purchase? Anyone know the answer? 

On first purchase you get all the stuff that comes with DLC, after repeating purchase you get ONLY GoldStandarts


Still it is more profitable for us players than spending the same amount of money on gold standards only. Hehehe