On Fedora 21 (and probably others) /etc/localtime is no longer file copy, but a symlink to original timezone file. Using `cp` to change timezone here would override original file instead of just changing the timezone. Details: https://groups.google.com/d/msgid/qubes-users/4a0de9457e08b93d1a39ac4cdbc6b632%40ruggedinbox.com