Room service is available 24 hours a day. You can always order coffee. We thought it was fun to order on your tv. We had a golf outting planned in Bermuda on our first cruise on Celebrity Zenith. All we had to do is go to the room service screen on our tv and order what we wanted. They asked for a 30 minute timeline. For example, breakfast (exact pastry pieces ordered) delivered between 6 am and 6:30 am. It came 6:15 am. It had everything we ordered on the tray. So anytime you want coffee, just turn your tv on!