Reminder that "UB-0X" are just codenames, not these things' real names. So just because both roach waifu and johj are called "UB-02" doesn't mean they're the same entity that somehow changed forms.

Since they're version exclusives, it's safe to assume that you don't meet Expansion in Moon or Beauty in Sun (at least not in the same circumstances you find them in their native versions), so it wouldn't make sense for one version to jump straight from UB-01 to UB-03, without a 02.