I did my adventuring today before KoLmafia knew about the new underwater zone. I kept getting errors when I tried to adventure there because my familiar could not breath. I traced this down to BBS being active and BBS was explicitly unequipping the bathysphere because it was checking my_location.environment against "underwater". Since this was an Override Zone and adventuring was fine without a familiar my hypothesis is that the override data did not return "underwater" for the environment.