Deletions will cascade to lower levels, so while I think that you can still achieve what you want, it will take a few more steps.
I would suggest that you accomplish this by:
- Navigating to the subfonds description that will become the new fonds-level parent
- Using AtoM's button to Duplicate the subfonds - make any changes needed in the new description (such as adding a proper identifier; changing the level of description; etc) and save
- Back in the original hierarchy, navigate to the first intermediate level that will be a child of the new fonds
- Use the Move module to move it to the new fonds - this should also move any descendant records
- Make any changes you need to the moved levels (e.g. are the series becoming subfonds in the new fonds? do you need to update the identifiers? etc)
- You will need to repeat this for any additional intermediary levels - for example, if your subfonds had 3 series, do this for each series
- Repeat as needed across any other intermediate levels (like other subfonds levels in the original)
The other option is to try something like:
- Add the fonds to the clipboard and export
- Manually update the resulting CSV:
- delete the fonds
- update the target subfonds to be the new fonds as needed (change Level, edit anything else like identifier etc)
- update any row whose parentId value referenced the old fonds description to reference the now-promoted subfonds level instead
- cascade these updates down as needed
- Use the CSV validator in AtoM to make sure you haven't broken the CSV
- Ideally, make a db backup first and/or try importing your edited csv into a test instance so you can review the results
- When you are confident about the changes, import the CSV, and then you can delete the original hierarchy
Cheers,