Why does default Intracompany Balancing rules trigger when auto-intercompany is also working?

hi testing historical amount entry instead of rates on some account values. Noticed that the default intracompany balancing segment rules kicked in on the posted translation journal, even though the auto-intercompany balancing also create the usual balancing segment offsets. The default intracompany BSV entries were offsetting lines, but wouldn't expect them to post if auto-intercompany lines are also added.