I thought that typesetting should start after \startext and that anything before it should be ignored.
That is indeed the case with the following input:

ABC
\starttext
CONTENT
\stoptext

But add a \setupbodyfont and suddenly the ABC appears:

\setupbodyfont[lmodern]
ABC
\starttext
CONTENT
\stoptext

Is this correct behaviour?
It is a nuisance because this phenomenon causes a spurious blank page appears in my book.
It might be a recently introduced because I did not experience this in the past.

ConTeXt  ver: 2013.04.16 12:08 MKIV beta  fmt: 2013.4.16

Hans van der Meer