title: Using a snapshot as an upstream
body: <p>I have a git repository that my team has been working on. Let's call it the <code>main</code> repo. Now I needed few things done by externals, so I took copy of the files I had in the repository and just made a new one (let's call it <code>snapshot</code> repo).</p>
  
  <p>Now both repositories contain some changes, and I'd like git to understand that the <code>snapshot</code> repository's starting point is a specific commit of the <code>main</code> repo and then merge changes from both repos. Or cherry pick from the <code>snapshot</code> and then from time to time push a new snapshot there.</p>
  
  <p>How would you go about it? Or was making a copy already a mistake?</p>