If I recall her entry from Demihuman Deities correctly, she used to be banished from Realmspace - for several centuries - in the past (I think due to the actions of the Untheric pantheon in general, and Gilgeam in particular), but her name was kept in the minds of the Untheric people by Gilgeam's clergy still blaming her as the source of the peoples' problems. Ironically, this eventually led to a cult in her name that managed to restore her connection to Realmspace shortly before the earliest campaign setting.
During the Time of Troubles, she was initially defeated by Gilgeam, and she was temporarily banished from the realms, but she attacked him on the Outer Planes - where he'd just dropped from being an intermediate power to a demipower due to Ao's new rule about how divine rank was calculated - and slew him. At that time, the events of H4 Throne of Bloodstone happened, and she was briefly reduced to being a demigod herself, meaning that she had to wait a year to send a new avatar to consolidate power on her behalf.
...none of which explains the retcon of "current" banishment.
