# How can I print print a calendar double-sided (duplex)?

To print a Filofax-like calendar I installed the package tex-archive/macros/latex/contrib/calendar. Processing

\documentclass[German,a4paper]{weekly}
\begin{document}
\begin{weekly}
{pageheight=5in,pagewidth=3in,firstday=4,punchgroups=1,punchcluster=6,intraspace=0.75in}
{}
december 24 2015 to january 6 2016
\end{weekly}
\end{document}


with LuaLaTeX (almost) did the trick:

But: Cutting out the two-page printout, folding it in the middle and glueing the result back to back would be fine. Except, that this would make a calendar twice as thick as a commercial product.

Duplex-printing (short-edge) prints January 3rd and December 31st at the back sides of December 24th and December 27th respectively which does not help at all.

Question: Did I miss any parameter to create a useful result?

BTW: The file demowkly.tex (contained in the package) yields the same problem, regardless whether processed with LaTeX/dvips/ps2pdf or with LuaLaTeX.