Complex sentence: In January 2003,2-504 PIR was operating from Bagram Air Base, while the 3-504 PIR was operating from Kandahar Air Base, Afghanistan in support of Operation Enduring Freedom.
Split into simpler sentences: In January 2003, the 2nd Battalion, 504th Parachute Infantry Regiment was operating from Bagram Air Base. While the 3rd Battalion, 504th Parachute Infantry Regiment was operation from Kandahar Air Base, Afghanistan in support of Operation Enduring Freedom.