Regions of data storage involved with fast replication relationships are managed and tracked in order to maintain the integrity of the data on the source and target volumes. In response to a delete operation referencing specified regions of storage, pending fast replication transfers are completed for source regions, fast replication relationships within the specified regions are withdrawn, and the specified regions of storage are release for subsequent allocation and reuse. The present invention facilitates maintaining synchronization of the storage management components of operating systems with the fast replication mechanisms of storage controllers, and releases unused storage regions for subsequent use. A storage subsystem may receive a delete command and make a determination of whether to release the specified regions of storage according to a state of a fast replication relationship with the regions of storage.