Problems with at night temperature

I'm having problems setting the "at night" colour temperature on my iPhone, running iOS 9.1

I set the ""at night" temperature to 4000K (to match my other devices), however the the display fluctuates (ha) around 2200k. Setting to the maximum 6500k still shows 2200k?? The temperature seems to refuse to set the ""at night" temperature to what I want :(

Location services, notifications, background app refresh and cellular data enabled in settings

See screen shot

lorna

This is the "wind down" mode based off your wake time. It's set to match the OSX f.lux, but Windows doesn't have this option yet. You can turn it off by selecting "dawn" for your wake time, and then you can set at night to whatever you want with no transition.