Currently, we can upload new nonconstituent relationships in bulk. However, you need to go in manually to each record and link/merge the nonconstituents afterwards. There's the Merge Non-Constituent Record but that's a cleanup tool. I want to avoid the cleanup by doing it right the first time.

We should be able to define one Unique ID for a new nonconstituent record, and use that so all relationships point to the same nonconstituent record.