Four hours will be more than enough. The station is about a 3-5 min walk from the baggage claim. If you bought the full priced ticket, then there is no need to wait more. If you bought a discounted ticket, then you will be tied to the exact train that you bought.
"You know, I was thinking about maybe taking the train and I want to be comfortable, but I need a goood price so we should probably get a reservation in regular class - oh and where are I going, Stuttgart, but the main station, not any other station like the trains sometimes stop at that are in the middle of nowhere, because it is incredibly cold today and I don't want to get stuck in . . ."
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I recently had a conversation with the CO elite line in a room full of Portuguese, Spanish and Brazilians, 90% of whom speak good English. After telling the CO agent my PNR in phonetic alphabet and going through the process of changing my award rez I hung up. Out of the ten or so people I had maybe five comments that I was speaking extremely quickly. I told them that I normally speak slower and use simpler vocabulary with them and that now they know how their Portuguese sounds to me when they don't do the same
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