Parent file snap when subfile snaps have already been done

I store my data on a dedicated partition J: mounted with veracrypt.
I want to snap it using kopia.
It was more convenient for me to begin by creating various snaps of all subfiles included in J: (ex J:\pro, J:\photos).
I completed all those snaps and checked that all files were fully uploaded.
I then tried to create a snap of J: thinking it would use the snaps mentioned above. However, kopia started from scratch has if J: 's subfiles snaps were not taken into account.
Could you please help me on this?

I use Kopia 0.9. on windows 10.
I tried both through UI and CLI

Today Kopia will not automatically reuse snapshot manifests of child directories if they exist, but that’s something that certainly interesting and could be done.

Regardless, Kopia will still deduplicate - it will not reupload the data from previous snapshots - it will simply need to recompute the hashes to confirm they match.