Ut-oh It was not intended to be an abuse: This is how PR's or done all the GH projects I am on as a commiter. It is a branch in the repo so like you have always done with patches, you or any of the PMC)can make change to it if need be. It is PR to master in the same repo. The process is simple: review it (fix it if need be), merge it and delete the branch.
Then you should do that. I won't