There’s no reason you can’t flush in a station - modern trains don’t just drop onto the track (and people have to work on the track, so the station is just a PR

There’s no reason you can’t flush in a station - modern trains don’t just drop onto the track (and people have to work on the track, so the station is just a PR thing to avoid offending passengers) In the U.K. any train from the last 30 years fills a tank, like an RV, including ones with physical locks.