Final answer:
The wear out date for the UCP ACU was September 30, 2019, after which U.S. Army soldiers were required to transition to the OCP.
Step-by-step explanation:
The Universal Camouflage Pattern (UCP), also known as ACU (Army Combat Uniform), was the standard military camouflage pattern used by the United States Army for their combat uniforms. The wear out date for the UCP ACU was officially set to September 30, 2019. After this date, all soldiers were required to transition to the Operational Camouflage Pattern (OCP), as the UCP was phased out in favor of the new pattern which offers better concealment in various environments.