A few days later on January 10, they released another teaser titled Number 2 or #2, which revealed their comeback date as February 5, 2020.
On January 8, 2020, Blockberry Creative announced that the leader HaSeul would be sitting out from promotions for health reasons.
[3] On February 5, the day of the song's release, Loona planned to hold a showcase for "So What" at 8:00PM.
Due to COVID-19 concerns, on February 2, Blockberry Creative announced that the showcase was canceled for fans, and it would be held without them as planned.
[5] On March 12, 2020, Loona received their first music show win on Mnet's M Countdown with the song.