Some discussion here: http://svn.haxx.se/dev/archive-2012-06/0481.shtml
Apparently, the LastChangedRev (LCR) of 'subdir' is not bumped to what it should
be (though the working revision is bumped), in the originating working copy,
after doing something like this:
(assuming dir/subdir/file.txt are versioned, and working rev is 2)
svn mv dir dir2
echo blah >> dir2/subdir/file.txt
svn commit -mm
After this, subdir has working rev 3, but LCR 2 in the originating working copy.
However, in the repository the LCR of subdir is 3 (and so it will be in any
other up-to-date working copy). Further updates to the originating working copy
will not repair this situation, because the working rev is up-to-date.
This issue did not occur with 1.6.