bold with \qtyrange{}{}

[Haines Brown]

I'm using siunitx package and in the body I have the expression:

\textbf{Time: \qtyrange{1}{6}{PM}} . The "Time" amd "to" are bold, 
but the 1PM and 6PM are not. How do get them to be bold as well?

  \documentclass[12pt]{memoir}
  \usepackage{siunitx}

  \begin{document}

    \textbf{Time: \qtyrange{1}{6}{PM}}

  \end{document}

Is there any advantage of qtyrange over SIrange?


-- 

     Haines Brown