On February 22, 2014, Oban was appointed by President Aquino to head the Visiting Forces Agreement Commission.

He earned his Master's degree in Business Economics at the University of Asia and the Pacific in Mandaluyong in 2005 when he was then the 5th Fighter Wing's Director for Operations.

He also served as a special assistant to the Minister of Trade and Industry from 1984 to 1986, and thereafter as the military assistant to the deputy defense minister before becoming the group commander of the Defense Intelligence and Security Group from November 1986 up to January 1988.

[5] Oban played a major role in the negotiation with Magdalo rebels involved in the Oakwood mutiny in 2003.

He also served as the Deputy Chief of Staff for Plans, J5, and is viewed by many as the perfect back-stop for Former Philippine Air Force (PAF) Chief Lt. General Oscar Rabena, a member of PMA Class 1978 who was also the top AFP planner before he was named to lead the 17,000-strong major service command.