Sergeant Major Estupinan enlisted in the Marine Corps in 2002 and completed recruit training at MCRD San Diego, CA during October 2002. Following recruit training, Private Estupinan attended Marine Combat Training at Camp Pendleton. Upon completion, he was assigned to Naval Aviation School in Pensacola, FL. After graduating he continued his MOS training in New River, NC and received the MOS 6122. Private First Class Estupinan was meritoriously promoted to Lance Corporal for graduating top of his class.
Lance Corporal Estupinan reported to Marine Helicopter Squadron 1, Quantico, VA in March of 2003 as a Power Plants T-58 Mechanic. Lance Corporal Estupinan was promoted to Corporal in 1 March 2004 and shortly after transferred to directly support presidential operations. Corporal Estupinan was promoted to Sergeant on 1 April 2006. During this time he served as the Collateral Duty Inspector and Power Plants division NCOIC.
Sergeant Estupinan was then selected for Marine Corps Recruiting Duty in October 2008. Sergeant Estupinan reported to Recruiting Station Lansing on January 2009. He served as a Canvassing Recruiter and a Recruiting Substation SNCOIC. Sergeant Estupinan was meritoriously promoted to Staff Sergeant 2 July 2011.
In February 2012, Staff Sergeant Estupinan reported to Marine Aviation Logistic Squadron 36, Okinawa, Japan where he served as a Power Plants SNCOIC and Hazardous Material Coordinator for Marine Aircraft Group 36.
In November 2013, Staff Sergeant Estupinan reported to Marine Aviation Logistic Squadron 39, Camp Pendleton, CA where he served as Power Plants Quality Assurance Representative and Marine Fleet Administrator.
In February 2015, Staff Sergeant Estupinan reported to Marine Medium Tiltrotor Squadron 268 where he served as the Phase Crew Coordinator.
In October 2015, Staff Sergeant Estupinan reported to Marine Medium Tiltrotor Squadron 165 where he served as the Phase Crew Coordinator, deploying twice with the unit in support of Operation Inherent Resolve. Staff Sergeant Estupinan was promoted to Gunnery Sergeant on 1 September 2016. Gunnery Sergeant Estupinan served as Maintenance Control SNCOIC and Flight Line Chief. In November 2020, Gunnery Sergeant Estupinan attached and deployed with the 11th Marine Expeditionary Unit serving as the Quality Assurance Chief for the Aviation Combat Element. Gunnery Sergeant Estupinan was promoted to First Sergeant on 21 December 2021.
In February 2022, First Sergeant Estupinan reported to Detachment 1, Landing Support Company, Fort Buchanan, PR serving as the Inspector-Instructor First Sergeant. First Sergeant Estupinan was promoted to Sergeant Major on 21 January 2025.
In February 2025 Sergeant Major Estupinan reported to Headquarters and Headquarters Squadron, MCAS New River, NC serving as the Senior Enlisted Advisor.
First Sergeant Estupinan has a Bachelor of Science in Political Science and personal decorations include the three Navy and Marine Corps Commendation Medal, and a Navy and Marine Corps Achievement Medal.