In general Duplicati is very robust at handling interruptions. I PERSONALLY am not aware of any actual data loss, though I have seen some posts about “expected synthetic files” and things like that, but most of them sounded fairly simple to resolve. Again, no data loss, just Duplicati saying “hey, I found a half a file left over my last run - please tell me what to do about it”.
I haven’t used --auto-cleanup myself but according to what the ‘help’ says, it sounds like what you’d want:
If a backup is interrupted there will likely be partial files present on the backend. Using this flag, Duplicati will automatically remove such files when encountered.
You might also want to try using the search option to search for ‘interrupt’ which will give you a few other posts such as these: