Thank you @Tony,
In my case I didn’t copy any directories, just copied some files into a folder that I had expanded merely a few seconds earlier. Maybe the local directory was still being indexed which caused some race conditions leading to some files being treated differently than the others.
Anyway, I wonder what file attributes and why could have been deemed different in my scenario. The files’ content, sizes and dates are the same. I think it could be great if there were a way for the user to force odrive to apply this more lenient comparison logic when necessary. Otherwise, I’m wasting many hours and even days of time and gigabytes of traffic on an operation that I know for a fact is useless. Do you think it makes sense for me to open a feature request for this?