In BMC Helix Operations Management, to use the new configurations added to the policy in the upgraded KM, you will clone the policy and create a new one by using the cloned policy.
In TrueSight Operations Management, you can change the KM version in an existing policy and configure the new configurations added in the upgraded KM.
In both the cases, you can also leave the existing policies as is and create a new policy to utilize the new features.