Simplify a deliver operation with a rebase operation

A rebase operation can simplify an alternate-target deliver operation when a sibling stream needs to configure changes from a related stream (see the following figure).

Because streams D1 and D2 are siblings, stream D2 can deliver its activities to stream D1. However, stream D2 contains changes in it foundation baselines that are not in stream D1. If stream D2 were to deliver activities a1, a2, and a3 to stream D1, all the additional activities in baselines in PA.BL2 would have to be delivered also.

However, if you rebase stream D1 to the baselines in PA.BL2 in the common parent stream before delivering the activities in stream D2, this complex alternate target deliver operation can be simplified. During the rebase operation, the changes in activities b1, b2, and b3 are preserved. After the rebase operation, no activities other than a1, a2, and a3 have to be delivered from stream D2 to D1.