A method of destage management of redundant data copies in a cache storage subsystem includes providing a plurality of target storage devices, each of the plurality of target storage devices capable of storing a complete copy of a data image. The data image and the plurality of target storage devices are subdivided into a plurality of sub-regions, each of the plurality of sub-regions organized such that a minimum cumulative total of the plurality of sub-regions on the target storage devices equals a number of sub-regions required to form the complete copy of the data image. Data is destaged from a write cache to the plurality of sub-regions on the target storage devices in an order such that a minimum number of sub-regions can be combined to restore the complete copy of the data image.