For SEO purposes, Google's John Mueller indicated on Twitter that he would advocate changing URLs again, then changing them back, and repeating the process. The person wanted to do it for SEO testing, but changing URLs is not a suggested method for SEO unless you are resolving a problem of some type.
He emphasized that when you start changing URLs, each new URL must acquire its own set of signals but it can redirect the old URL to the new one, but if it's simply changing the URL to see how things work before changing it back and said to be not a good idea.