I had booked a Christmas (December 22nd - January 2nd) round trip to Ireland from Vancouver (BC) via London for myself & my toddler and my husband (two individual bookings) in the summer of 2012.
I was notified by email of minor changes: eg connecting flight leaving a half an hour later.
I checked a week before we were to fly out and saw my return flight had been changed to August 30th!
I immediately called customer service and told them about this mistake; they put me on hold for 5-10 minutes then told me the system was down and I should call back later.
I called back the next morning and told them about the mistake; they told me I had requested this change. This was untrue. I got annoyed

. They started looking into it. I was on the phone for nearly an hour. They told me they were starting to fix it but it would take a couple of hours to show up online.
I had to call again that evening (20-30 minute call) to have them finish making the correction and reissue the ticket.
I`m still shocked; not by the mistake made with the date, but by the belligerent and completely unapologetic customer (dis)service staff.