[2] The 8000 series trains were introduced between 1989 and 1990, initially operating as seven-car sets.

[1] Between March 2010 and November 2012, the fleet gradually underwent refurbishment, which also included interior changes.

[1][3] Since 2018, the fleet has been receiving LED destination displays and updated interior lighting.

[4]: 3 In 2017,[4] car 6 of each set was modified to become a "Premium Car" with 2+1 abreast reclining seating ahead of the introduction of reserved-seating limited express services on 20 August 2017, which incurs a surcharge.

[5] To accommodate the cars' modifications, the fleet was provisionally operated as seven-car sets from September 2016.