

does not mean that they have to take any steps to contribute the changes they’ve made to the upstream project.
You’re partially right. They don’t have to “contribute back” by submitting pull requests or something similar.
They do have to contribute back by making their changes publicly available. Whether upstream uses those changes is up to them.
I’m going to ignore you now since all of your replies have shown me you’re a moron. Peace.
I’ve never been a fan of hackathons or sprints.
Slow and steady wins the race.