My wife and I will be flying in June-July on the following award tickets: LAX-YVR-FRA-SIN-CGK [destination]-SIN-LHR [stopover]-YYC-LAX. The flights will be on AC, LH and SQ (made back when you could do this for 65k apiece in economy).

Yesterday I received a "Reservation Change Notification" showing that our SIN-LHR flight on SQ had been dropped. I checked on SQ's website and saw that the flight had not been cancelled, so I called United and they re-added that flight segment.

I asked the agent why this happened, and what surprised me was her answer. She seemed surprised and said, "It seems an agent cancelled the flight. To what end I do not know."

Any thoughts on why this happened? I did change the date of the LHR-YYC-LAX flights back on March 14 (without adding additional miles) but I just received the change notification yesterday (July 30).