When verifying that error messages appear correctly when each of the sections of the annotation form are too long, when testing a body that was too long (over 64,000 characters), I had selected "No Competing INterests" and left the COI box blank; however, the error message that was generated read,
"Your comment is 84784 characters long, it can not be longer than 64000.
You must say something in your competing interest statement."
When I replicated this, with the COI radio selection to "No" and nothing in the COI box, the error message appeared correctly (i.e. just the part about too many characters).