Why some commuters don’t need to wait until 9:30am for cheaper train tickets

Every morning after the main rush hour, people can be seen loitering outside tube stations waiting for the 9:30am off-peak prices to kick in — but not every station is the same.
Photo by Steph Gray on Unsplash
Some stations on the edges of London could have a lengthy wait for the first train to leave after 9:30am, so they have different rules for when the off-peak prices can apply.
But only for people making several trips during the day.
At some stations, a person tapping in before 9:30am