Shifting an encoded data slice subset for smart rebuilding

A computing device of a storage network, the computing device comprises:

• memory;
• an interface;
• and
• at least one processing module operably coupled to the memory and the interface, wherein the at least one processing module is operable to:
• generate a second encoded data slice of a second subset of encoded data slices of a set of encoded data slices, wherein the second subset of encoded data slices is not currently stored in a set of storage units of the storage network, wherein the set of encoded data slices include a first subset of encoded data slices that is stored in the set of storage units and includes at least a decode threshold number of encoded data slices of the set of encoded data slices, and wherein a first encoded data slice of the first subset requires rebuilding;
• and
• send, via the interface, the second encoded data slice to the set of storage units for storage therein, wherein when the second encoded data slice is stored, the second encoded data slice is no longer included in the second subset of encoded data slices.