UPDATE - Bad News, but not horrible...
From the forum:
The release of the first piece of singleplayer DLC, the Faction Pack, has unfortunately suffered a delay . It was planned for "June" but there were some challenges. We're all working on it, but it looks like it should be ready for the middle of July now.
I'm really sorry about this delay, especially if you were one of the people who bought the Season Pass as soon as it was available, and like the rest of you I would've preferred if the first Pack would've made the month of June.
I do hope that after Metro: Last Light, you can wait a few more weeks for us to complete everything for the Faction Pack and do all the additional testing required to ensure it will be as high quality as possible!
Until we have a final release date set in stone, I don't have many other details to share right now for the Faction Pack. There will be more news and screenshots to come before the Faction Pack is released, but I don't know when that will be exactly.
The DLC achievements can be found on Steam, however: http://steamcommunity.com/stats/Metr...t/achievements
All the other DLCs in the Season Pass should follow over the course of 60 days after the Faction Pack has been released.
Another piece of news that was shared is:
Warning: Spoiler! (Click to show)
The Librarians will make a return to the DLC missions in some capacity