I've just uploaded a new version of crda (3.13-1) to Debian, which is
now under the copyleft-next licence.
I had some questions about how Debian can comply with this licence,
which I raised in
<https://lists.fedorahosted.org/pipermail/copyleft-next/2014-August/000782.html> etc. Ubuntu/Canonical may have similar or different issues with the licence; as I am not an Ubuntu developer I can't judge this.
In any case, if crda in Ubuntu ever has Ubuntu-specific patches, you
will need to update the source URL in debian/copyright accordingly. It
may be sensible to do this preemptively.
One of the nice things about standards is that there are so many of them.