The meetingpoint is at Bus station IJzijde (Platform L)at the back of Amsterdam Central Station.
Take the entrance at Amsterdam centre and walk through the station to the river side or use the bike /pedestrian tunnel at the west part of the station to the ferries. When you come out the station go to the escalator (the escalator is near Service and Tickets /AH ToGO) of the bus station and you will see Majel at the West part of the Bus station Ijzijde (near platform L) at the top with the sign Wetlands Safari.