I haven't figured it out yet, but there seems to be a bug between Org and Org-Journal. Both recently got updated to the latest versions and then I noticed that org-deadline would have a problem with the version number. I believe that Org-Journal installs a function into a hook for (in)visible text which is causing the problem.
Does anyone recognize this? Forgive the poor bug description, I deleted org-journal from .emacs.d/elpa to stop Emacs from setting the hook, so, when I have time, I'll try again. -- David Masterson