Maybe we're also in a situation that, let's say, half of the group wants to graduate and the other half wants to carry on. If that was the case, Up Front would be in a weird situation since a group with only 4 members doesn't seem to be a thing nowadays (or only part-time, like Country Girls). The possibilities would be either dissolving the group and adding the remaining members to other groups (like Kobushi/Rei) or adding new members. That was something Kobushi didn't want so they ended the group, but maybe the members of Kobushi are more open about this option.
Or maybe they really want to set another mood after Risa's departure. I would have prefered a great comeback with the 8 members instead of the announcement of an audition, but well.
Your post makes me think about two things:
- I saw this K-pop girl group called Aespa debut with 4 members over 2 months ago and, well, thinking about it again makes me feel like 3-6 members is the ideal amount of members for a group...
- While Tsubaki Factory debuted in 2017 with 9 members, one of them - Risamaru - left the group last month, thus making it an 8-membered group; I feel like this is similar to that one time from 2014 when one of the members of Girls' Generation (Jessica) left, thus making that group's member count go down from 9 to 8. Therefore, I might as well compare Tsubaki's situation to that of Girls' Generation considering how both groups used to have 9 members, but currently only have 8...
Sorry if my thoughts seem out of place because, lately, I've been in a K-pop mood the way rurupedia is .