On September 4, the group released the music video for "Hotter Than A Summer", a reggae track composed by Red Roc and written by YE YO.

[7] On December 25, 2015, the group released a Christmas special clip [8] to the song 안아줘, from their EP, Showtime.

On November 27, 2015, Woojoo sprained her ankle while practicing dance moves causing the group's next comeback to be delayed.

On February 3, 2016, Wassup released a collaborative single with Madtown and Rooftop House Studio, titled "Do You Know How I Feel" featuring Jooyi, a former member of Rania.

[10] The company announced that the group would be coming back as a quartet composed of Nari, Jiae, Woojoo and Sujin, but did not make any statement regarding Dain and Jinju, leading to speculation that they had left as well.

On February 2, it was announced that Dain and Jinju had also filed lawsuits to terminate their contracts,[11] to which the company revealed that the group as a whole were still 500 million won in pre-debut debt.

[12] On March 31, Wassup pre-released the track "Dominant Woman" a single part of their third mini-album titled ColorTV set to be released, on April 13, 2017.

[22] And in 2016 Sujin participated in the Legend Hero Samgugjeon series as Lina, a great national idol.

In 2017 Sujin participated in dramas The Happy Loner as Park Yeon-hee, Introverted Boss as Mi Bae, and Lingerie Girls’ Generation as Kim Eon-Joo.

On February 11, 2022, main vocalist Jiae announced a Makestar project to fund her debut solo album.