Why is this sentence 'her train is leaving tomorrow at 10AM' correct? [closed]

Solution 1:

When we use the present continuous to talk about a plan in the future, it is called Future Arrangement Present Continuous in English grammar. It is used to emphasis that you are certain that something will happen, to the point that you can talk about it as if it's already happening in front of your eyes.

BBC English explanation

Both "will be leaving" and "is leaving" are correct, but the latter implies more certainty, and is less formal. The Present continuous for future arrangements is usually used in spoken English.