Is it correct to say "We will be arriving into <station>"?
Solution 1:
This seems to be the accepted railway jargon for main-line London stations (possibly other stations too). This is probably due to the fact that Euston, like Paddington, Kings Cross, Waterloo, Liverpool Street etc is an 'enclosed' station, which is a terminus.
Having said that, and not being a regular rail-user myself, I suspect that the idiom is employed elsewhere, for large city stations. I would be interested to know if it is used for stations which are not termini.
I'm not sure why but 'into Euston' seems to carry a more portentous significance than 'at Euston'.
Solution 2:
You are right; customarily we would arrive at the station or stop (at, as the station represents a point on the line), and arrive in a neighborhood, city, or larger area (in, since you are surrounded by it).
On the other hand, the action of travel lends itself to into, because you are physically entering something or somewhere:
- I drive into town.
- I walk into a restaurant.
- I ride into the mountains.
- I fly into an airport.
- I pull into a driveway.
Where the mode of transportation is known, it would not surprise me that arrive gets substituted; the passengers on that train are not suddenly going to arrive by stagecoach, and the announcement needs to be clear that the train is in fact arriving somewhere, not for example stopping for a moment to let another train pass.
Besides, I could argue that arriving into is slightly different from arriving at. In the last minute or so before my train pulls up at Penn Station, I'm clearly inside the station— I can see the signs and people waiting on the platforms— but we haven't stopped and the doors haven't opened. We've arrived into the station, since we're inside of it now, but we haven't arrived at the station till we're at a fixed point.
Solution 3:
At is definitely the preferred form when describing approaching the platform itself (at least in AmE…).
But, as you are arriving into the station I don't think you can argue it semantically. You are literally heading into a structure.
Think of it as an extension of "What time does the train get in at the station?" You wouldn't find fault with that statement (at least I wouldn't). You see two different choices in that statement.
Hence, I think the chosen preposition is a bit fluid when it comes to train stations. You arrive at the platform but at or into the station.