Great question because this has haunted me for over 10 years with cookiecutter. Most of the time I was copy-pasting newer features from running projects back into the template, and then copy-pasting in other running projects.
But Keel is based on copier which has a "pull" based approach. It means unlike cookiecutter where you generate project from template once, you can run `copier update` to update your project with the latest addition to the template. (It takes care of merging based on the initial config that you selected).
It's just running one command `copier update`. Docs here: https://django-keel.readthedocs.io/en/latest/?h=copier+updat...
You don't need to fork it unless you want to make some improvements or build upon the base template itself.