[user2634]

"Set up git" instructions tell this:

  git config --global user.name "Your Name"

  git config --global user.email [e-mail]

You have to use same email as in registration or else it won't push.

[getsat]

Nope. Authentication is done using your ssh key pair.

All my commits are done by [e-mail], but that is obviously not my Github email on either my personal or work accounts.