Currently we don’t support reordering relations, see the following troubleshooting article. Any previous implementation was actually not intended, we do eventually plan to look into it but for right now we don’t support it. Troubleshooting - Strapi Developer Documentation
Hello @DMehaffy,
just to let you know the solution I went for as the order was mandatory in my case is that I added a step in the beforeUpdate lifecycle of the Model to check and handle the order changed by the user.