Most of our guild events start at 20:00 BST but it's always worth double checking when you signup. If the event does start at a different time I will always write a note in the event description to warn people.
For anyone who wants an easy <Belsavis: Heroic Missions>, take the mission called "Rock and a hard place". All you need to do is enter the instance, walk 60 meters, just run past adds, and click a console. Takes 20 seconds for 1000 conquest points.