I have no previous knowledge about the issue, other than to say that
on mac osx 10.4 and earlier, the file would be overwritten, but it
wouldn't update automatically in acrobat or apple's pdf reader,
preview. One workaround I found was to open the pdf in a web crowser
that can open pdf's (like firefox) and then just refresh the page. I
don't know if that would work for you, but it might be worth a try.