Overview
- The single was released at 6 p.m. KST on Feb. 25 across major online music platforms.
- It includes the title track Bloom Hour and the B-side Mirror, which sends a message from the present members to their past selves.
- Leader Exy participated in writing the lyrics, framing the music around time shared with the fanclub Ujung.
- Members, including Bona and Eunseo, describe the release as a gift prepared for fans to celebrate the milestone.
- Starship shared mature concept photos on official SNS featuring a celebratory cake, as WJSN issues its first group release since 2022's Sequence.