This probably makes the most sense to me. But I also think depending on caffeine to wake up keeps the brain from transitioning from sleep to a full waking stat

This probably makes the most sense to me. But I also think depending on caffeine to wake up keeps the brain from transitioning from sleep to a full waking state. I can't seem to give up coffee, but I notice if I cut back it is not as severe. Also, going to bed early enough so that by the time you wake up, you have had time to run through the final dream REM stage of sleep before waking up helps tremendously.