"051 - White leather kate054001_1_1.jpg": the index is inside 054001 (set 054, image 001) and _1_1 repeats it, but only a suffix equal to the whole number before counted as a repeat, so the set kept 054001 and every image was a release (Duke's threads: 2,791 releases of 3,251 files). A suffix that the number before ends with is a repeat as well. Both implementations; tests; fixtures identical. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>