[3] It is a long-term aspiration of Merseyrail to complete the electrification of the Northern Line to Wigan.

[6] Proposals to extend Merseyrail's Northern Line to a new terminal station at Headbolt Lane, between Kirkby and Rainford, were announced in 2007[7] but did not receive funding until 2019.

[8] Headbolt Lane station became the new terminal interchange between trains from Liverpool and Wigan/Manchester when it opened on 5 October 2023.

[3] Trains originate at Blackburn and join the Kirkby branch at Wigan Wallgate, having travelled via Todmorden, Manchester Victoria, Atherton and Hindley, and change direction at Headbolt Lane.

[14] In the May 2023 timetable, trains mainly continue beyond Manchester to/from Blackburn via Todmorden and Accrington.

[15] As of 2023, the standard service on the Kirkby branch is hourly, with trains starting from Blackburn and terminating there on the return journey.