I have one in my account.

The original itinerary (ticket #2) was auto-canceled due to a schedule change of a different itinerary (ticket #1) since the new time of ticket #1 would meant missing ticket #2. Asked an UA agent to reinstate ticket #2, and canceled ticket #1 after reinstatement.

To this date, having already flown the itinerary, my account still shows it in the future flight credit section. Not a big deal to me.

The interesting part of the auto-cancellation -> reinstatement - the updated ticket booked into a higher fare bucket, and I got more PQPs than what I paid for