Effective 13 May 2024, he serves as commander of the "South Sudan Stabilization Mechanism", an observer force to ensure adherence to the peace agreements.

[2] Before that, he served as the Ugandan commander of the UPDF forces in the Democratic Republic of the Congo under the joint Uganda/DRC mission code named Operation Shujaa.

[5][6] Immediately prior to that assignment, from April 2015 until October 2017, he was the commanding officer of the third army division of the UPDF, based in Moroto.

[1] In 2006, when the Uganda Junior Staff College, based in Jinja, was founded, Lieutenant Colonel Olum was selected to be its commandant.

[12] In 2012, the African Union (AU) established a 5,000-strong military force, based in Nzara, South Sudan, with the objective of hunting down fugitive warlord Joseph Kony.