\input{umtest-preamble}
\usepackage[bold-style=upright]{unicode-math}
\setmathfont{Cambria Math}
\begin{document}
\[\mathbf\GREEKmath\]
\[\mathbf\GREEKtext\]
\[\mathbf\greekmath\]
\[\mathbf\greektext\]
\end{document}