When adding a new release or editing an existing release, the "guess case" button on the main page appears to work, but doesn't actually apply changes when saved.
I discovered this when I added this release:
I used the "guess case" button for the release, but had to manually edit the release group to match. After saving, the release group was correctly capitalized but the release was not. When I tried to correct it (again using the guess case button), the edit summary showed no changes (I tried with both regular and beta). Once I corrected it manually, the edit summary was correct and it's now fixed: