The sub-group made their simultaneous Japanese and Korean debuts with the single albums Koi no Sign and Azure.
Infinite F was officially announced at the One Great Step Returns encore concert, held February 28 and March 1.
On October 14, Woollim Entertainment officially announced that Infinite F will be debuting in Japan with Koi no Sign on November 19.
[4] As part of Japanese promotions, a pop-up store was set up in Harajuku from November 17 to 30, selling various Infinite F goods and clothing items.
On November 5, the album cover for Azure was revealed, closely followed by the announcement that Infinite F would be debuting in Korea the following week.