We have known for a long time that we (my T1D son) were slow to respond at night: from 45 minutes our response time to turning the corner goes up to 60-75 minutes.
Over the past few months, we have also figured out that our CF (correction factor) doubles at night: we use twice as much bolus insulin to drop the same amount. It is not good for us because we are typically cautious at night with corrections: this CF doubling often causes us to be needlessly careful.
We always thought that both of these were due to sleep. But the surprising thing we have recently discovered is that both facts, for us, are also true at night when we are awake: they appear to be connected, with us, to circadian cycles rather than sleep.
Is this also true for you, or is it a YDMV fact? Are you insulin-resistant and slow to respond to insulin at night? Is it associated with sleep or with time?