This discussion may contain spoilers!
The group that attacks Bonnie and Co?
The attackers simply attack on sight, and Bonnie seems to know well enough to run at the first sign of trouble. Sort of seems to match the level of fear inspired in the face of the cabin crew.
Could be a long shot, but we don't really know what the purpose of that attack was. And it could provide another connection between 400 days and S2. And we still don't know what was stolen. Could be something important that may come into play later in S2 also.