On Sun, 23 Feb 2014, tclug at freakzilla.com wrote:

> Like I said, I don't think it's an unlimited skip, and some versions 
> might be better at it than others. I used do-release-upgrade -d, and it 
> worked for me. Might not have worked as well in previous versions.

That is sort of consistent with what happened with my 12.04.2 LTS going to 
14.04.  It probably has something to do with it being LTS.  The other two 
were not LTS and they did not try to skip.

Clearly, the man page for do-release-upgrade is not correct in stating 
that the -d option will "Check if upgrading to the latest devel release is 
possible."  It almost always checks only for the next release from 6 
months after the installed release.

Mike