Original sentence: The Sandringham line runs at 9-minute frequencies in the weekday peak period and is the only line in Melbourne to operate on a 20-minute frequency at night, and does so seven days a week
Edited sentence: It is the only line in Melbourne to operate on a 20-minute frequency at night, and does so seven days a week.Most services stop at all stations, however there is one limited express each morning.The Sandringham line runs at 9-minute frequencies in the weekday morning peak period, and 10-minute frequencies in the evening peak period