How to change subsection title within a frame through overlay in beamer?

Question

On a given beamer slide with three bullet points that are uncovered sequentially, I want the subsection title to alternate with every new bullet that shows up.

\uncover<1>{\subsection{Subsection title A}}
\uncover<2>{\subsection{Subsection title B}}
\uncover<3>{\subsection{Subsection title C}}
\begin{frame}
\begin{itemize}
\item<1>Bullet A
\item<2>Bullet B
\item<3>Bullet C
\end{itemize}
\end{frame}

I already tried several variations of \uncover, like \only, \onslide, \visible.

Answer 1

Slides are elements of frames and frames are elements of subsections. What you try to do is to make the same frame an element of three different subsections relating to the slide number. This is probably not going to work, since subsections are usually meant for navigation and Table of Contents purposes and this would make them pretty uncomfortable. As being completely subjective and with no offense, I think this is also along the lines of a bad style. Nevertheless, you can take the obvious path

\documentclass{beamer}
\useoutertheme{smoothbars}
\begin{document}
\section{Section Title AAA}
\subsection{Subsection title A}
\begin{frame}
\begin{itemize}
\item Bullet A
\invisible{\item Bullet B}
\invisible{\item Bullet C}
\end{itemize}
\end{frame}

\subsection{Subsection title B}
\begin{frame}
\begin{itemize}
\item Bullet A
\item Bullet B
\invisible{\item Bullet C}
\end{itemize}
\end{frame}


\subsection{Subsection title C}
\begin{frame}
\begin{itemize}
\item Bullet A
\item Bullet B
\item Bullet C
\end{itemize}
\end{frame}
\end{document}

I have chosen a random outer theme such that the subsections are visible. If you don't want these intermediate subsections to appear in the ToC use the starred versions e.g. \subsection*{Subsection Title A}

Answer 2

With \againframe and overlay specifications, you define your entire frame once, but show only parts of it at a time. See the Beamer User Guide, for version 3.12, Section 11.2, Repeating a Frame at a Later Point.

In the example below, when we define the frame, we show only the first slide of the frame. Later we call \againframe to show the second one in the second subsection, and the third one in the third subsection.

\documentclass{beamer}
\useoutertheme{smoothbars}
\begin{document}
\section{Section Title}
\subsection{Subsection title A}
\begin{frame}<1>[label=spam]
\begin{itemize}
\item Bullet A
\item<2-> Bullet B
\item<3-> Bullet C
\end{itemize}
\end{frame}

\subsection{Subsection title B}

\againframe<2>{spam}

\subsection{Subseciton title C}

\againframe<3>{spam}
\end{document}

Is it good style? I don't know. I use it as a kind of elaborate table of contents. I have a quite big figure showing different things, and come back to it several times to show details of different parts.