Creating a new branch seems to update all tickets with old commits

Old issues are being updated with commits when a new branch is created.

For Quiz (from drupal.org instructions)
git checkout 7.x-4.x
git checkout -b 7.x-5.x
git push -u origin 7.x-5.x

For example
https://drupal.org/comment/8662807#comment-8662807

Even though, when you look at http://drupalcode.org/project/quiz.git/shortlog/refs/heads/7.x-5.x

The commits only go back to the 7.x-4.x branch.