Sep 15, 2014 - 07:20 AM
If you are purchasing a ticket from the airport to the main station, those tickets are good for 2 months from the date of purchase so you can use it at any time whether your flight is delayed or arrives early.
If you are traveling on from the main station, you should allow yourself plenty of time for baggage and customs plus the time it takes for the train to the main station. We usually recommend 2 1/2 to 3 hours. If you arrive in the main station early there are several places to get a snack to tide you over.