Automatically download collab repo updates

I would like to automatically backup my Unity Teams projects as updates are posted to them to my own physical server as well.

I know projects can be updated by opening an editor of the correct version, or exporting from the cloud console. However I am looking for a way to do this via a web request or command line.

I know that using GitHub for repo through Unity would likely allow me to do this, but I am looking for a solution that won't involve disrupting many existing projects which are stored on Unity's servers.

My best guess is to setup a webhook for project updates, then have that open an editor on my server in headless mode to perform the update. The main issue with this solution would be needing to keep a current Unity editor version for every project on the server.

If anyone knows how to accomplish this without GitHub that would be greatly appreciated! Any ideas are also welcome.