This post does not specify what happen on a `git fetch all`. I suppose it takes the first one, and you have to specify other remote entries if you want to pinpoint the remote repos to use ?
Note that the deploy I mention will do a fetch, so this solution does not replace the fallback variable.
Past that I've not used it that often outside of having a cheap cluster solution in a way. Try it out and let me know!
We do not use github only for issues and PRs, though, but also with repos hooks : pushing to a branch trigger a build on our CI, which then deploy our staging env if successful.
Of course, we could do as well with git hooks and writing code to do the web push. I just can't see any reason to migrate to that.
I guess I'll have to look into what ElasticBeanstalk is doing.