For some reason I had to delete my old nose art from the folder before the new one took effect. This could be because I sometimes experiment and rename the original to test out my work. Anyhow, squadees knew right away, when I told them that I was seeing the old nose art. So, I suspect that I was not alone.
Remember always make a copy of anything that you plan to remove or delete, and save it in a good place, just in case.