Why is it “will be” instead of “is” here?

Question

This is an announcement I heard in a subway car I got on in Tokyo today:

Next stop is ABC, and the stop after ABC will be XYZ.

I'm not sure if the English sounds natural to native speakers, but if it does, then I wonder why "will be" is the appropriate usage in this case instead of "is". Is there any logic behind?

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POST EDIT (On January 2, 2021)
I would like to add that the subway train I took was not an express but a local one that stops at every station. I thought that it was obvious, from the signboards at the stations or the train route maps posted inside the train car itself, that the stop after ABC is XYZ.

Answer 1

I've heard this with trains, where a particular train on a line isn't necessarily going to stop at every station, so the passengers need to know in advance what the train is going to be doing. So this stop is X, the next stop will be Y informs people of what's happening, and also gives them a chance to get off the train if they're about to go a lot further than they wanted to!

But as well as that, it's a natural way to talk about the future. I know it might sound strange (isn't the route planned? Don't they know right now what the next stop will be?) but it's not unusual. It has a friendlier and more polite sound - you'll often hear things like the store will be closing in five minutes, versus the store is closing in five minutes which sounds much harsher and almost confrontational. Obviously the next station is [whatever] doesn't have the same sense of "so you'd better get out!!" but will be still has that professional, polite air to it.

Also, and I don't know if this actually applies to your subway specifically, you could have a fixed way of talking about stations to make things consistent and clear to riders. Always saying this station is X, the next will be Y makes it explicit that if you hear is then they're talking about the current/upcoming station, and will be means the one after that. This can be important on trains where people can only hear part of an announcement, and you don't want them to be confused about whether X is this one or the one after

Answer 2

"is" would be proper grammar in this case too, but "is" would have a different meaning.

The meaning of "is" could be used in a sentence something like the below:

In this line, the next stop is ABC, and the stop after ABC is XYZ.

"will be" is more towards the meaning of like "the subway car's next stop would be anywhere but it will be XYZ stop. Whereas "is" would be more towards the meaning of like there is a metro and the next stop has to be XYZ because it can't wander off to another stop.

"is" would mean the next stop always gonna be XYZ, whereas "will be" means that this time it will be the stop XYZ.

So "is" wouldn't fit in your sentence because the subway car is not stuck on a path, it can go to any stop.