Rule for cont'd footnote not working as expected

See the attached screenshots. I've set my footnotes not to have a rule above them unless a note splits across a page (column). I occasionally have places, though, where a rule is appears a new footnote. I'm doing a lot of page reflow as I put layouts together for our typesetter, so I'm trying to figure out whether this is just ID's compositing software getting overheated (seems unlikely), or me not understanding footnote formatting as well as I should (almost certain.) Whatever help I can get is, as always, much appreciated.

Rob

P. S. Maybe once I'm retired and not having to pump out the work everyday, I can come on here more often to answer a few questions, but for now I owe all you guys.