Get the first (and last) page number of an arbitrary section and subsection anywhere in a Beamer document

Question

For example, I would like to print out, on the first frame of section X, and again the first frame of section X-subsection 1, the beginning (end) page number of section X, subsection 1. Can I do that?

In the following example, I would want to print "Section 3, subsection 1 starts on page: 5" on page 4 and page 5 and the numbers will be updated if the structure is updated automatically.

\documentclass{beamer}
\setbeamertemplate{footline}[frame number]

\begin{document}

\section{section without subsections}
\begin{frame}{section without subsections}
    slide 1
\end{frame}

\section{section with subsection starting right away}
\subsection{subsection at the beginning of section}
\begin{frame}{section with subsection starting right away}{subsection at the beginning of section}
    slide 2
\end{frame}

\subsection{section with subsection starting right away}{second subsection}
\begin{frame}{second subsection}
  slide 3
\end{frame}

\section{section with subsection starting later}
\begin{frame}{section with subsection starting later}{section with subsection starting later}
    slide 4
\end{frame}

\subsection{section with subsection starting later}{first subsection after a slide}
\begin{frame}{first subsection after a slide}
    slide 5
\end{frame}

\end{document}