London Reconnections is an absolute gem of a site for any of our Capital’s train geeks. You’ll find on their blog a plethora of London related railway paraphernalia, history, and operational studies. They also provide an insight into what might be coming in the future, including articles on line upgrades and service improvements.
This particular article looks at the complicated nature of off-peak services and delves into which lines provide the best service frequency and suggests which others may see improvements in the future.
It’s certainly worth a read, if purely for the link to the map of London Underground’s hottest tunnels!