From the first page of the PDF:
The citizens of Neverwinter are killing each other, and only you can end the insanity. A Living Forgotten Realms adapted adventure set in Neverwinter for characters levels 1-7. This adventure is found in Issue 195 of Dungeon online, part of D&D Insider. Dungeon issues may be found on the Wizards of the Coast website (http://wizards.com/dnd).
The stat blocks in the published adventure support characters of levels 3-5 (AL 4) and this adaptation document presents adjusted stat blocks for AL 2. Therefore, the adventure can be played at either AL 2 or AL 4; any legal table of characters levels 1-7 can play. At least one person at the table (either a player or the DM) must have an active subscription to D&D Insider. We recommend that you allow at least twelve hours of playing time to complete this adventure (the equivalent of a three-round LFR adventure).