Obviously with the news of the 360 gen matchmaking services going down next year there are many of us trying to grind out remaining achievements. I and everyone I’ve matched with recently in Halo: Reach have ran into the problem when trying to complete the “One Down, 51 to go” achievement that weekly challenges simply don’t show up in the challenges list. There are only daily challenges, and one challenge for completing all daily challenges, but no weekly challenges to be seen.