My father was caught out with these changes the other day AKL-CAN-LHR was booked with 8hr layover and only by accident noticed the flight to London was changed to a day later. This was 3 days out from departure. I had a feeling something wasn't right as his transit accommodation booking had disappeared from the app around a month ago..
On a slightly different topic, I'm not overly happy that the A330 from Beijing to Istanbul has changed to a 2-2-2 business class config for my flight early Jan. Yuk