This is a suggestion for the main site. It would be wonderful if we could not only delete a pre-uploaded photo, but also replace it. The difference would be that by replacing no comments or would be lost.
As scanning needs some more time than just registering, people could delay the scanning process without risking to add a new photo “too late” (after others liked the card or even commented). The only working method right now is to delete the pre-uploaded photo and leave a sad gap in the wall.
I support that - sometimes people mix cards up and upload a wrong picture, might be even as a replacement. To avoid that someone might end up with pictures they don’t even know on their favorites, we’d need a notification every time a favorited or commented photo would be replaced. Just my thoughts on this.