iOS accessibility nav bar title swipe down not working

I'm using the rotator tool to enable swipe up or down between accessibility elements with accessibility trait set to .header. This works fine - in both up and down directions for cells within a tableview. And it works fine when you transition from the first cell UP to the nav bar title. But if you then try to swipe DOWN from the nav bar title to the first cell, it says "heading not found" and remains stuck in the nav bar. Left / right swipes transition correctly across all elements.