[3] By 1920 Henry Barracks became a sub-post attached to Fort Brooke in San Juan where the 65th Infantry First Battalion were posted.

By that time the combat troops stationed at Henry Barracks consisted of an artillery battalion and a heavy mortar company.

A full complement of the Army phased out its presence at the post in 1965 when the base was transferred to the General Services Administration for decommission.

A heliport, maintenance shop, administration offices and a NGX PX are some of the facilities at the National Guard post use mostly for monthly drills.

The University of Puerto Rico at Cayey hosted the U.S. Army Reserve Officers Training Course ROTC program at a site in the former Herry Barracks base.