Hi Sindar,
Check this link will give you an idea about bandsteering
Low : Attempt steering towards 5GHz, but allow clients on 2.4GHz sooner
Normal : Attempt steering towards 5GHz, but allow clients on 2.4GHz after a few attempts
Aggressive : Aggressively attempt steering towards 5GHz, delaying new 2.4GHz associations longer
Thanks,
Ashok Kumar