I get the feeling I am way off base with this question... but here goes some more thoughts...
I am entertaining this idea for our daily OSSV backups
1. Find any long running backups that are incomplete
2. Abort/Stop
3. NDMPCOPY current snapshot data for qtree to a staging volume
4. modify snapvault relationship to new location
5. update
- Meanwhile the other snapvault relationships can continue with their daily updates
6. Upon completion of the update in the staging area, reverse the above process moving it back in the normal volume