Ontario: no limitation period for possessory liens

In Edan Agency Inc. v. Palinkas, the Court of Appeal held that limitation periods do not “generally” run against possessory liens.  This is because such a lien is a defence, and defences are not subject to statutory limitation periods.

This is a settled point of law.  Accordingly, it’s curious that the court should have used the qualifying language of “generally”.  I’d like to know in what circumstance a possessory lien would be subject to a limitation period–I suspect there’s none.