I applied PlusPoints to my daughter's reservation 3 weeks ago for our next Tokyo trip and have been checking loads regularly and seeing the waitlist notations on the segments every time I checked. Well, today I got an alert from seats.aero that PZ had opened so I logged-in to my UA account only to find that she was no longer waitlisted. I immediately reapplied the PPs but the PZ space was already taken.

Has anybody seen anything like this before, where you are removed from the waitlist randomly?