Just before 6pm, secret yourself at a discreet location close by.
At 6 on the dot, everyone puts on a winter hat and heads to the published coords for a quick chat and to decide on a drinking establishment to meet up in after the event.
At 6:14 group photo.
At 6:15 on the dot everyone is to remove hats and move on to chosen watering hole if they wish.
Groundspeak are giving out Souvenirs for your profile as well.