I currently have all my photos uploaded in High Quality in Google Photos. I initially used Picasa to organize them into albums from my folder structure. After they stopped supporting Picasa, I would manually uploaded via the web interface. I recently got a Pixel (which allows unlimited original), so I copied all my photos to my Pixel and had it upload all of the to Google Photos in Original quality.
I THOUGHT that Google Photos would be smart enough to detect duplicates and replace the High Quality with Original, but it did not, and now I basically have two copies of all of my photos with Originals all unlabeled.
Every "solution" I have found online is old, involving use of Picasa or Google Drive.
Is there any solution out there for my issue? Perhaps something via the API?
The only other thing I can think of is to delete everything, re-upload, manually label which of course is not ideal.