GTR (Southern Railway & Thameslink) have announced today (8/11/25) in an e-mail that they are gradually reinstating the half-hourly service during the weekdays from 14 December 2025 for the East Grinstead line (including Riddlesdown). But there are some catches!
They advise;
“Services between East Grinstead and London Victoria – Monday to Friday
To make it easier for people to travel during the middle of the day, services between East Grinstead and London Victoria will now be half-hourly during the middle of the day on weekdays, rather than hourly.
This change will apply Monday to Friday during school holidays, and on Thursday and Friday during term time.”
At the moment the new timetables are not online, but more information is on this link for Southern;
https://www.southernrailway.com/service-updates/timetables
Thameslink is on this link; https://www.thameslinkrailway.com/service-updates/timetables