Show fields for adding & editing only if blank

​Ok, I think I follow you.
As a follow-up question, if I change the relationships to not use proxy fields, am I still able to do conditional filtering?

The layout is as follows:

The lists in the type dropdowns are conditional upon the client selected.

This shows me only the Job Contacts (for example) for client ABC when that client is selected, and does not show me the Job Contacts for client XYZ.

Would I still be able to do a conditional filter if I don't use proxy fields?

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Andrew
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