Al-Barnawi is the son of the late extremist, Mohammed Yusuf. ISIS appointed him a leader in 2016 after he led several loyalists out of Boko Haram.
The restructuring, ordered by the ISIS headquarters in Iraq, followed the death of ISWAP commanders in battles with the Nigerian military.
An emergency meeting was attended by Wali (Leaders), Qa’ids (Chiefs), commanders and heads of units, according to PRNigeria.
Ba-Lawan will lead the fight for the ISIS-backed Islamic Caliphate of Africa (Wilaya of Africa), covering parts of Nigeria, Chad, Niger and Cameroon.
Malam Bako is the new Deputy (Na’ib) to Command the ISIS Caliphate Command of Nigeria (Wilaya of Nigeria), recently established at Tumbuktu Triangle in Southern Borno.
Abba-Kaka was named Governor of Tumbumma. He will oversee Marte, Abadam, Kukawa, Magumeri and other parts of Lake Chad; and Abubakar Dan-Buduma is the new Operation Commander, Timbuktu Triangle.
Ibn Umar is now Chief Prosecutor, Abu Umama becomes Amir of Tudun Wulgo, while Muhammed Maina is the Commander of Sabon Tumbu.
The ISWAP council also introduced Mobile Courts and policies to harmonise all insurgent activities and groups.
The body has stepped up plans to establish two Wilayas (Caliphates) at Lake Chad and Sambisa forest to sustain the war against countries in Sub-Saharan Africa.
New taxes and levies have been imposed on the Borno communities as part of the regulation of trade and agricultural activities.
ISWAP members will henceforth collect N5,000 monthly from traders and farmers; fishermen will pay N2,000 per bag of fish, among other levies.