I'm wondering if PEP440 should recommend how to version forks? It's fairly common to fork dependencies temporarily until the change can be released upstream.
Ideally, you want to version a fork (and keep the same name) so that it fulfills the requirement, but be obvious that it's a fork.
Although pip allows overriding requirement consistency, consistency is preferred, and needed in cases where a `pkg_resources.require` enforces it in a console script.
As it is now, the "post-release" scheme works for this, but it's not the intended use case.
Marcus