You have to redefine the footline beamer template and define a new beamer template for the bottom right corner. Then you can easily change the content of the bottom right corner with \setbeamertemplate{right corner}{•}
.
\documentclass{beamer}
\usetheme{Boadilla}
\setbeamertemplate{right corner}{%
\insertshortdate{}\hspace*{2em}%
\insertframenumber{} / \inserttotalframenumber%
}
\makeatletter
\setbeamertemplate{footline}{
\leavevmode%
\hbox{%
\begin{beamercolorbox}[wd=.333333\paperwidth,ht=2.25ex,dp=1ex,center]{author in head/foot}%
\usebeamerfont{author in head/foot}\insertshortauthor\expandafter\beamer@ifempty\expandafter{\beamer@shortinstitute}{}{~~(\insertshortinstitute)}
\end{beamercolorbox}%
\begin{beamercolorbox}[wd=.333333\paperwidth,ht=2.25ex,dp=1ex,center]{title in head/foot}%
\usebeamerfont{title in head/foot}\insertshorttitle
\end{beamercolorbox}%
\begin{beamercolorbox}[wd=.333333\paperwidth,ht=2.25ex,dp=1ex,right]{date in head/foot}%
\usebeamerfont{date in head/foot}\usebeamertemplate{right corner}\hspace*{2ex}
\end{beamercolorbox}}%
\vskip0pt%
}
\makeatother
\begin{document}
\begin{frame}{Frame 1 - Default}
Frame Content
\end{frame}
{
\setbeamertemplate{right corner}{\insertshortdate{}}
\begin{frame}{Frame 2 - Date only}
Frame Content
\end{frame}
}
\begin{frame}{Frame 3 - Default}
Frame Content
\end{frame}
\end{document}