the ideal of getting up at 0930 when you didn't fall asleep until 0500 is that you'll only be a little bit sleepy but you'll have plenty of time to do fun things and may even fix your sleep schedule a little.
the reality is that you spend most of your time awake zoned out, feeling sickly and strained, and doing nothing but laying in bed staring at social media until you accidentally nap for several hours