A question that is often asked within the train travel community but not only is if a

train can leave the station early?

The short answer is Yes and No. The trains are running by a rigid timetable schedule which is hard and time consuming to be modified. But there are few exceptions…
I know, it’s confusing.
Let’s see when a train can depart the station earlier than scheduled.
One scenario where such a train can depart early is if the train is scheduled to only drop off passengers, then the train might leave earlier than scheduled.

Is this Amtrak message familiar to you?

“Stop for passenger discharge only; train might leave earlier than scheduled”

Another scenario where a passenger train can leave the station early is

when the train is arriving late in the upcoming station.

Example:
Train Y was supposed to be in Station X at 12:00PM with a scheduled STOP of 20 minutes, departing time would be at 12:20PM, however the train has a delay of 10 minutes, now because of the delay the train leaves the station within just 10 minutes after it arrived. Technically the train leaves on time, but it leaves before you expected.
This can happen both ways, if a train arrives early in the upcoming station, the STOP will be longer, practically it has to “waste” some time in the station so it will stay on schedule.
If a train will only get passengers (not discharge) in the upcoming station, it can leave a few minutes earlier if all the passengers are accounted for and all the luggage were loaded, I am talking about reservation only type of travel.
Basically a schedule is set so everybody that interacts with the train knows what to expect, otherwise it wouldn’t be a schedule anymore. However as I have mentioned above, there are some exceptions where the train may in fact leave the station early.

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