I don't know why my Eightline change to terminal male. I think they all will develop to terminal male, per experiences of advance wrasse keepers. There are multiple Terminal male in my 320 DT, but I recently lost the blue throat. One day he just not there anymore. I think somehow he got eaten by one of the carpets.
Wrasses won't live past 5-7 years. It is nice to get female or Juvenile and watch them turn to male. I just got another juvenile Eightline. Right now I am still undecided if I should leave him in separate tank or put her into the main DT with the wrasses (and the male Eight-line)