Map of the Angolan Civil War during February 1980 - September 1981.
With Cuban support for Angola dwindling after the two unexpected Shaba invasions, UNITA saw an opportunity to breathe and reform their guerrilla war. Establishing their headquarters at Jamba in the remote southeast part of the country, UNITA began their offensive for territorial control. Meanwhile, South Africa, after conducting several raids against SWAPO, began preparing for a larger cross-border operation.
Sources used:

Adrien Fontanellaz's and Tom Cooper's "War of Intervention in Angola: Volume 2 - Angolan and Cuban Forces at War, 1976-1983"
John Turner's "Continent Ablaze: The Insurgency Wars in Africa 1960 to the Present"
Stephen Weigert's "Angola: A Modern Military History, 1961-2002"
Own work
Rr016