JOINT BASE SAN ANTONIO-CHAPMAN TRAINING ANNEX, Texas -- Col. Mark Estlund, 960th Cyberspace Operations Group commander, hands the 42nd Cyberspace Operations Squadron guidon to Lt. Col. Jeremiah Flerchinger, signifying his assumption of command of the 42nd COS, June 5, 2022, Scott Air Force Base, Illinois. The 42nd COS is a geographically separated unit of the 960th COG located at Joint Base San Antonio-Chapman Training Annex, Texas