OK; what should it be called?
What are "relief lines"
Doesn't the Great Western Main Line also carry freight & other services?
How should that be renamed?

No
There should only be one railway=station, but there can be multiple building=train_stations, per station.

See also multiple building=school objects within one school site.

Could you check please. i think you added the incorrect Glanyrafon wiki tags.

Thanks. Done

Hi
building=train_station

Hi
What is "Cup of Tea"
Cafe?

Please don't add railway=station tags to buildings. There are already station nodes.

Hi
'Ticket office' is not it's given name. Please revert.
Add facilities as nodes within the building:

shop=ticket

amenity=vending_machine

Please don't delete valid data (ref:crs from railway station tags)

Please don't add railway=station to train station buildings
"It should be mapped separately from the railway=station tag as they may have different names.

There may be multiple train station buildings per railway station "

building=train_station

Hi
Please use train_station instead of railway_station.
building=train_station

Hi
Please use train_station instead of railway_station.

building=train_station

Hi
Please don't change train_station to railway_station.

building=train_station

Please don't change train_station to railway_station.

building=train_station

There's already a railway station

You've doubled up on buildings again. Please ensure you download all objects in JOSM

There was already a residential area.How come you didn't see it in iD?

Hi
It would be great if your changesets didn't span continents. Please close one & then start another.

Could you please review/repair your edits around this railway station. You've misaligned track & added buildings/bridges where there are none.
osm.org/#map=19/51.36164/0.75671

Hi
way/804171380
This is not a building & there is already a railway station tag.
Please ensure you have full knowledge of the items you're amending. Most new contributors start with a couple of items close to where they live