Cannot use endextracode in tikz-timing

The manual claims that extracode could be ended by endextracode so one may add more rows after some TeX-thing happens.

But this code does not compile. Seems like the function of & was not switched back.

documentclass{article}
    usepackage{tikz-timing}
begin{document}
    begin{tikztimingtable}
        A & 10M \
    extracodeendextracode
        B & 20M \
    end{tikztimingtable}
end{document}

The log file is even more interesting:

 Missing character: There is no B in font nullfont!
 
 ./Untitled-6.tex:7: Misplaced alignment tab character &.
 l.7        B &
           20M \
 ?

Actually I did not find any single piece of working example. I guess this is the expected syntax?

By the way, I am using MacTeX and I just updated my packages.

documentclass{article}
usepackage{tikz-timing}

makeatletter
@ifpackagelater{tikz-timing}{2020/10/01}{}{%
deftikztiming@endextracode{tikztimingtable@row}%
}
makeatother

begin{document}
    begin{tikztimingtable}
        A & 10M \
extracode
    relax
endextracode
        B & 20M \
    end{tikztimingtable}
end{document}