math-style=ISO, \mathup, \mupPi and \upPi

[ghost]

Continuing https://github.com/wspr/unicode-math/issues/509 (which was closed by the originator), I wonder whether I could kindly ask the authors to update the documentation and/or the behavior so that they match. As of now, texdoc unimath-symbols mentions \mup... for Greek letters, but not \up... for Greek letters. texdoc unicode-math does exactly the opposite, mentioning \up... for Greek letters, but not \mup... for Greek letters. Before reading https://github.com/wspr/unicode-math/issues/509, I was confused.

Further, \mathup doesn't print anything for capital Greek as of now, even if you load a math font. Running {xe|lua}latex on the input file

\documentclass{article}\pagestyle{empty}
\usepackage[math-style=ISO]{unicode-math}
\begin{document}
\begin{itemize}
\item \textbackslash mupPi: \(\mupPi\)
\item \textbackslash mathup\{\textbackslash Pi\}: \(\mathup{\Pi}\)
\item \textbackslash mathup\textbackslash Pi: \(\mathup\Pi\)
\item \textbackslash upPi: \(\upPi\)
\item \textbackslash symup\{\textbackslash Pi\}: \(\symup{\Pi}\)
\end{itemize}
\end{document}

produces an output in which only the last two items have the effect desired (and the first item is covered by https://github.com/wspr/unicode-math/issues/509 but not documented otherwise):