From 1989, the first phase of the project to re-lay and double-track the line, mostly in a new alignment with wider curves, longer tunnels and bridges, was launched on three sections between Sin-ri, at the end of the Jeonju realignment, and Suncheon.

[7][11] On September 1, 2010, the South Korean government announced a strategic plan to reduce travel times from Seoul to 95% of the country to under 2 hours by 2020.

[13] Yeosu hosted the Expo 2012, and Korail timed the introduction of Korea Train Express services on the line ahead of the event.

[10] Original plans foresaw the start of Jeolla KTX services in April 2011, reducing the Seoul–Yeosu travel time to 2 hours 55 minutes, using KTX-II (KTX-Sancheon) high-speed trains.

[14] In February 2011, when the necessary electrification works were 96% complete, the start of services was postponed to September 2011, and the Yongsan–Yeosu travel time was planned to be 3 hours 7 minutes.