On April 27, 2024, Sonray Music announced that BUS had formed sub-units, namely BUS5 and BUS7. BUS5 consists of Heart, Jung, Jinwook, Phutatchai, and Marckris. BUS5 released their single on May 1, 2024. Meanwhile, BUS7 consists of Alan, Khunpol, Thai, Nex, Copper, Aa, and Peemwasu and released their single on June 5, 2024.