Hey, something similar for me too! I used to do close-open shifts working at a grocery store, while also doing all-nighters constantly in highschool and college because I'm a chronic procrastinator. And then I started to work at Activision on the night shift, with day shift friends/roommates. I worked 10 hour days 8 days straight with a rotating day off every pay period, for 6 weeks. So I'd usually get to sleep at 6am and wake up at 2pm.

My insane trick/strategy to swap between day shift and night shift activities is to stay awake for 24 hours. I'd do it to get adjusted after coming back from vacations, to make appointments, and any other reason I needed to be awake before noon