The behavior Im seeing is that, with a disk full of alpha and beta images (300 GB), when I limit to 20GB, it deletes 20GB of images. leaving 280 GB of images on disk. When I limit to 10 GB it deletes 10 GB of images, leaving 290 GB of images on disk.
I would expect the rule to delete 280 GB of images instead, leaving 20GB of images on disk.
The code you linked is what tells the rule to run or not run, no? Is it the same code that runs while the rule is actively deleteing as well?