It's possible that the AA element is being rendered in a different order than it was before. This could affect the Ancestor Count, Ancestors Text and Match Index values from what you have currently selected. Try removing as many filters as you can get away with, and it will (usually) speed up the matching while increasing reliability.
One quick and easy way to see what's changed without breaking anything, is to add a child element and respy it after the initial one is no longer working. Apply all of the same filters (Do this manually rather than copy/pasting the mask, as that may overwrite some of the new data), then sort by the checkboxes as you currently are. Click between the two elements and it should become apparent what's changed and what's reliable.
