Eledmac line numbering out of margin at top of column (memoir)

Question

I'm using eledmac to typeset a doc with two columns in memoir. The first line number at the top of the right column continues to be placed to the left of the column, as it was with the left column, rather than in the margin to the right. The same is true for the left column beginning on the second page (its first line number continues from the right column on the preceding page to be placed to the right of the column). I thought of using the \multicol package, but I need to use eledmac for the line numbering / critical apparatus. I also tried eledmac's \linenummargin command, but without success. Sure I must be missing an easy workaround. Appending a mwe:

\documentclass[letterpaper,12pt,twocolumn,landscape]{memoir}
\usepackage{polyglossia}
\usepackage[parapparatus]{eledmac}
\usepackage{lipsum}
\usepackage{verse}
\setlrmarginsandblock{.75in}{.75in}{1} 
\setulmarginsandblock{.75in}{.75in}{1} 
\checkandfixthelayout 
\setcolsepandrule{28pt}{0pt}
\setcounter{firstlinenum}{1}
\setcounter{linenumincrement}{2}
\lineation{page}
\linenummargin{right}

\begin{document}
\chapter*{Hello World}
\beginnumbering
\pstart
\lipsum
\pend
\endnumbering
\end{document}

and images of the much improved result thanks to David Carlisle's helpful responses (now it is just the top # on most pages that is off):

Answer 1

The original version is at the end, this version saves the page as well as line number in the position information sp it can cope with the line number being re-set

\documentclass[letterpaper,12pt,twocolumn,landscape]{memoir}
\usepackage{polyglossia}
\usepackage[parapparatus]{eledmac}
\usepackage{lipsum}
\usepackage{verse}
\setcounter{firstlinenum}{1}
\setcounter{linenumincrement}{2}
\lineation{page}
\linenummargin{right}



\makeatletter


\def\eldefkey{\romannumeral\line@num @\romannumeral\c@page}

\let\saved@affixline@num\affixline@num
\def\affixline@num{{%
\pdfsavepos
\edef\tmp{\write\@auxout{%
\gdef\string\eldef \romannumeral\line@num @\noexpand\romannumeral\c@page
{\noexpand\the\pdflastxpos}}}%
\tmp
\expandafter\ifx\csname eldef\eldefkey\endcsname\relax
\else
 \ifnum \csname eldef\eldefkey\endcsname=3818782 % 3818782
          \@firstcolumntrue
 \else \ifnum \csname eldef\eldefkey\endcsname=25445662 % 19514654
     \@firstcolumnfalse
 \else \ifnum \csname eldef\eldefkey\endcsname=5653790 % 5653790
          \@firstcolumntrue
 \else \ifnum \csname eldef\eldefkey\endcsname=27280670 % 21349662
        \@firstcolumnfalse
\else
  \showthe\line@num
 \fi\fi\fi\fi
\fi
% force first number to first column
\ifnum\line@num=1
\@firstcolumntrue
\fi
\saved@affixline@num}}


\renewcommand*{\affixpstart@num}{%
    \ifsidepstartnum
        \if@twocolumn
            \if@firstcolumn
                  \gdef\l@dld@ta{\llap{QQQQ{\leftpstartnum}}}%
            \else
                  \gdef\l@drd@ta{\rlap{PPPP{\rightpstartnum}}}%
            \fi
        \else
             \@l@dtempcntb=\line@margin
            \ifnum\@l@dtempcntb>\@ne
                  \advance\@l@dtempcntb \page@num
            \fi
            \ifodd\@l@dtempcntb
                  \gdef\l@drd@ta{\rlap{XXXXX{\rightpstartnum}}}%
            \else
                  \gdef\l@dld@ta{\llap{YYYYY{\leftpstartnum}}}%
            \fi
        \fi
    \fi

}

\makeatother

\begin{document}
\chapter*{Hello World}
\beginnumbering
\pstart
\lipsum
\pend
\endnumbering
\end{document}

---

I didn't have the fonts so this is tested with the standard font setup, but appears to work. Not a complete fix but a manual work-around for when things go wrong, the code added in the preamble forces the line number 30 to switch sides.

\documentclass[letterpaper,12pt,twocolumn]{memoir}
\usepackage{polyglossia}
\usepackage[parapparatus]{eledmac}
\usepackage{lipsum}

%\setmainfont{Linux Libertine O}
\linenummargin{left}
\makeatletter

\let\saved@affixline@num\affixline@num
\def\affixline@num{{%
\pdfsavepos
\edef\tmp{\write\@auxout{%
\gdef\string\eldef\romannumeral\line@num{\noexpand\the\pdflastxpos}}}%
\tmp
\expandafter\ifx\csname eldef\romannumeral\line@num\endcsname\relax
\else
 \ifnum \csname eldef\romannumeral\line@num\endcsname=3818782
          \@firstcolumntrue
 \else \ifnum \csname eldef\romannumeral\line@num\endcsname=19514654
     \@firstcolumnfalse
 \else \ifnum \csname eldef\romannumeral\line@num\endcsname=5653790
          \@firstcolumntrue
 \else \ifnum \csname eldef\romannumeral\line@num\endcsname=21349662
        \@firstcolumnfalse
\else
  \showthe\line@num
 \fi\fi\fi\fi
\fi
\saved@affixline@num}}
\makeatother

\begin{document}
\chapter*{Hello World}
\beginnumbering
\pstart
\lipsum
\pend
\endnumbering
\end{document}