A little bird told me there is a way to get all of the mobs in 16-NiM EC to have the health of the mobs in 8-NiM EC. Switching from 8-NiM to 16-NiM after T&Z are dead didn't reset the health or title timer according to said bird.

I wasn't there so he could be lying but I'm sure that little bird's flock will tell you all sooner or later.