if an inline citation is created where the <ref> in all lower case is then followed by an ending </ref> that has one or more uppercase characters, then BIO CHECK will flag it as unmatched ref tags.
e.g. <ref>...</reF>
However, if there is an uppercase letter in the first <ref> tag, then it will NOT generate an error.
e.g. <Ref>...</ReF>
Maybe its one of my settings? The 870 question today reminded me to report this behavior.