Re HKG - to be safe, leave at about 6:00 AM, not later than 6:15, to arrive around 6:30-6:45 AM. The security lines at HKG can be long sometimes, even at that early hour. The lounge is comfortable (although far from the usual gate). You can have coffee and a light breakfast (cereal, toast, etc.) in the lounge, so you dont have to worry about getting up extra early for breakfast.