Last night I was awake in the middle of the night and could hear the pipes creaking. Usually all my heating and hot water is off overnight so I checked in the app and could see that my conservatory was at a manual override 16 degrees set point. This is the temperature it normally runs through the day but the set point changes it to a low (5 degree) overnight in the evening. I cancelled from the app and the heating turned off as expected.

This has happened once before and wonder what might cause it?