If no cifs shares or nfs exports it may work... need to test out vol move on a mirror volume (but may not work) in a vsim or the lab.
Typically, I cascade the snapmirror then update the new target from the original source and release snapshots. Cascaded mirrors work very well and we use them often to move mirror targets. Since all snapshots move with the cascade, you can update from the original source volume.
Test out on a test mirror. Should work but may have a restriction since I have t tested it. For cascaded mirror, no need to break. Can update from the common snapshot as well but more steps than vol move which would be easier.