It appears the release date for the InFamous: Second Son DLC, titled First Light, has been put up on the PlayStation Store. The screenshot (below) was sent to IGN by one of their readers and pegs the release as August 26th, which is a Tuesday so it lines up with the North American store update. If the date is correct then Europe would likely get it the day after on August 27th, in line with the store update here.
The First Light DLC was announced during Sony’s E3 conference, and it will focus on Fetch. She has the neon powers, and is one of the characters Delsin interacts with. However, this is set before the events of Second Son and will focus on Fetch’s stay in the notorious prison of Curdon Cay. We’re likely to hear something from Sony regarding this date soon, and we’ll update once this has been confirmed or denied.