Yeah, that's what I thought. The 'built-in' sleep data doesn't exist until after waking up for the day, which is useless in developing this feature. It requires Apple to do a complete rewrite of the underlying core to support 'live' or 'real-time' sleep info as the night progresses and as sleep is occurring to support, for example, 'wake me up after getting 7 hours of sleep'. The development effort to support this would be at least several months, in the current backlog at least a year out.