I have some large floats that look best on empty pages, i.e., pages that do
not have headers?

The wiki suggests that
location=page
will put the float on an empty page but this does not seem to be the case:

\starttext
\dorecurse{3}{\input knuth}

\startplacefigure[title=Cow,
location={page}]
{\externalfigure[cow.pdf][width=.7\textwidth]}
\stopplacefigure

\dorecurse{3}{\input knuth}

\stoptext

I am using the latest beta.

Alan