日頃 uplatex + upmendex + dvipdfmx でタイプセットをしております．
つい最近 pxjahyper がアップデートされましたが，どうも otf パッケージと相性が悪くなったようで，以下のようなメッセージが出てきます．
以下再現ソースと，コンパイル時のメッセージです．\documentclass[uplatex,dvipdfmx,ja=standard,11pt,b5paper,openany]{bxjsbook}
\usepackage[uplatex]{otf}
\usepackage[T1]{fontenc}
\usepackage{lmodern}
\usepackage[dvipdfmx, colorlinks=true, bookmarks=true, bookmarksnumbered=true, %
bookmarkstype=toc, filecolor=blue, urlcolor=blue, linkcolor=blue, %
linktocpage=true, citecolor=red, menucolor=black, %
pdfnewwindow=true, breaklinks=false]{hyperref}
\usepackage{pxjahyper}
\begin{document}
\section{はじめに}
\end{document}
> uplatex test.tex
This is e-upTeX, Version 3.14159265-p3.8.3-u1.26-191112-2.6 (utf8.uptex) (TeX Live 2020) (preloaded format=uplatex)
restricted \write18 enabled.entering extended mode
(./test.tex
pLaTeX2e <2020-10-01u04>+2 (based on LaTeX2e <2020-10-01> patch level 4)
L3 programming layer <2021-02-18>
(/usr/local/texlive/2020/texmf-dist/tex/latex/bxjscls/bxjsbook.cls
Document Class: bxjsbook 2021/02/02 v2.5 BXJS document classes
(/usr/local/texlive/2020/texmf-dist/tex/latex/tools/calc.sty)
(/usr/local/texlive/2020/texmf-dist/tex/latex/graphics/keyval.sty)
(/usr/local/texlive/2020/texmf-dist/tex/latex/bxjscls/bxjscompat.sty)
(/usr/local/texlive/2020/texmf-dist/tex/generic/iftex/ifpdf.sty
(/usr/local/texlive/2020/texmf-dist/tex/generic/iftex/iftex.sty))
(/usr/local/texlive/2020/texmf-dist/tex/latex/geometry/geometry.sty
(/usr/local/texlive/2020/texmf-dist/tex/generic/iftex/ifvtex.sty))
(/usr/local/texlive/2020/texmf-dist/tex/latex/bxwareki/bxwareki.sty
(/usr/local/texlive/2020/texmf-dist/tex/latex/bxwareki/bxwareki-cd.def))
(/usr/local/texlive/2020/texmf-dist/tex/latex/bxjscls/bxjsja-standard.def
(/usr/local/texlive/2020/texmf-dist/tex/latex/bxjscls/bxjsja-minimal.def)
(/usr/local/texlive/2020/texmf-dist/tex/platex/pxjahyper/pxjahyper-enc.sty)))
(/usr/local/texlive/2020/texmf-dist/tex/platex/japanese-otf-uptex/otf.sty
(/usr/local/texlive/2020/texmf-dist/tex/platex/japanese-otf/ajmacros.sty))
(/usr/local/texlive/2020/texmf-dist/tex/latex/base/fontenc.sty)
(/usr/local/texlive/2020/texmf-dist/tex/latex/lm/lmodern.sty)
(/usr/local/texlive/2020/texmf-dist/tex/latex/hyperref/hyperref.sty
(/usr/local/texlive/2020/texmf-dist/tex/generic/ltxcmds/ltxcmds.sty)
(/usr/local/texlive/2020/texmf-dist/tex/generic/pdftexcmds/pdftexcmds.sty
(/usr/local/texlive/2020/texmf-dist/tex/generic/infwarerr/infwarerr.sty))
(/usr/local/texlive/2020/texmf-dist/tex/generic/kvsetkeys/kvsetkeys.sty)
(/usr/local/texlive/2020/texmf-dist/tex/generic/kvdefinekeys/kvdefinekeys.sty)
(/usr/local/texlive/2020/texmf-dist/tex/generic/pdfescape/pdfescape.sty)
(/usr/local/texlive/2020/texmf-dist/tex/latex/hycolor/hycolor.sty)
(/usr/local/texlive/2020/texmf-dist/tex/latex/letltxmacro/letltxmacro.sty)
(/usr/local/texlive/2020/texmf-dist/tex/latex/auxhook/auxhook.sty)
(/usr/local/texlive/2020/texmf-dist/tex/latex/kvoptions/kvoptions.sty)
(/usr/local/texlive/2020/texmf-dist/tex/latex/hyperref/pd1enc.def)
(/usr/local/texlive/2020/texmf-dist/tex/latex/hyperref/hyperref-langpatches.def
) (/usr/local/texlive/2020/texmf-dist/tex/generic/intcalc/intcalc.sty)
(/usr/local/texlive/2020/texmf-dist/tex/generic/etexcmds/etexcmds.sty)
(/usr/local/texlive/2020/texmf-dist/tex/latex/hyperref/puenc.def)
(/usr/local/texlive/2020/texmf-dist/tex/latex/url/url.sty)
(/usr/local/texlive/2020/texmf-dist/tex/generic/bitset/bitset.sty
(/usr/local/texlive/2020/texmf-dist/tex/generic/bigintcalc/bigintcalc.sty))
(/usr/local/texlive/2020/texmf-dist/tex/latex/base/atbegshi-ltx.sty))
(/usr/local/texlive/2020/texmf-dist/tex/latex/hyperref/hdvipdfm.def
(/usr/local/texlive/2020/texmf-dist/tex/latex/rerunfilecheck/rerunfilecheck.sty
(/usr/local/texlive/2020/texmf-dist/tex/latex/base/atveryend-ltx.sty)
(/usr/local/texlive/2020/texmf-dist/tex/generic/uniquecounter/uniquecounter.sty
))) (/usr/local/texlive/2020/texmf-dist/tex/platex/pxjahyper/pxjahyper.sty
(/usr/local/texlive/2020/texmf-dist/tex/latex/etoolbox/etoolbox.sty)
(/usr/local/texlive/2020/texmf-dist/tex/latex/bxjatoucs/bxjatoucs.sty))
(/usr/local/texlive/2020/texmf-dist/tex/latex/lm/t1lmr.fd)
(/usr/local/texlive/2020/texmf-dist/tex/latex/l3backend/l3backend-dvipdfmx.def
(|extractbb --version)) (./test.aux)
*geometry* detected driver: dvipdfm
(/usr/local/texlive/2020/texmf-dist/tex/latex/graphics/color.sty
(/usr/local/texlive/2020/texmf-dist/tex/latex/graphics-cfg/color.cfg)
(/usr/local/texlive/2020/texmf-dist/tex/latex/graphics-def/dvipdfmx.def)
(/usr/local/texlive/2020/texmf-dist/tex/latex/graphics/dvipsnam.def))
(/usr/local/texlive/2020/texmf-dist/tex/latex/hyperref/nameref.sty
(/usr/local/texlive/2020/texmf-dist/tex/latex/refcount/refcount.sty)
(/usr/local/texlive/2020/texmf-dist/tex/generic/gettitlestring/gettitlestring.s
ty)) (./test.out) (./test.out)
Package hyperref Warning: Rerun to get /PageLabels entry.
(/usr/local/texlive/2020/texmf-dist/tex/platex/pxjahyper/pxjahyper-ajm.def
! Improper \spacefactor.
\bxjs@SE ->\ifnum \spacefactor
<\@m \spacefactor \@m \else \spacefactor \sfc...
l.39 \@
gobbletwo\if\if \def\pxhy@cond#1\fi{%
? x
No pages of output.
Transcript written on test.log.
ちなみに，pxjahyper を 57732 に戻すとこのエラーは発現しませんので，今はそのように対処しています．改善のアドバイスをお願いできればありがたいです．