In just 16 days.
2016 Upper Deck Marvel Masterpieces is now sold out on e-Pack, the company announced yesterday (August 4, 2016).
The e-Pack version of that series was released on July 20, 2016, which means that product was only on the market for 16 days.
Upper Deck didn't reveal their inventory count, but there's currently 130,588 cards from that series that's available for trade, which came from approximately 43,530 packs (3,628 boxes). Each pack contained 3 cards, while each box contained 12 packs.