Tomita Lab has announced that Isono, vocalist and guitarist for YONA YONA WEEKENDERS, will join the ensemble for "the birds of four live," a two-night concert series happening July 8-9 at Billboard Live venues in Tokyo and Osaka.

The addition comes after santa, the original vocalist for the Tomita Lab project, stepped back from both the group and S.A.R. earlier this month due to S.A.R.'s suspension of activities. Ticket holders who specifically wanted to see santa perform can request refunds through the Billboard Live website.

Isono isn't a stranger to Tomita Lab—the musician has previously collaborated with the project. For these upcoming shows, the full lineup includes Tomita Lab founder Tomita Keiichi (guitar, keyboards), alongside vocalists Arche, Isono, Hokumura Fuki, and Yō from Natsudaidai. The rhythm section features Uehara Shunsuke on drums, Suzuki Masato on bass, and Higuchi Naohiko on guitar, with Wakui Sara handling additional keyboards.

Each night will feature two sets—the first beginning at 5:30 PM and the second at 8:30 PM at both venues. This marks the first time the reconstituted ensemble will perform together publicly, positioning the concerts as an important moment for the project's next chapter.

Tomita Lab, known for its experimental approach to Japanese music, often brings together musicians from different projects for collaborative performances. This lineup adjustment demonstrates the project's flexibility in bringing in capable replacements while maintaining the artistic vision for the concerts.

For fans who had planned to attend specifically for santa's performance, the option to receive refunds acknowledges the significance of lineup changes in live music. For those interested in experiencing the reimagined ensemble with Isono's contributions, tickets remain available through the official Billboard Live channels.