A second expansion module was released in August 2009, bringing the British Armed Forces to the Syrian battlefield. This new module introduces units, vehicles and weapons currently in service with the British military, such as the Challenger 2 tank and Warrior IFV, and also includes the US IBCT. There is a new campaign from the British perspective, and new standalone scenarios. There are minor changes to the Syrian side, and the expansion patches the base game to version 1.20.
Source: Wikipedia, "Combat Mission: Shock Force", available under the CC-BY-SA License.