It’s great that your body can easily adjust to different schedules. You have a good balance and you’re intentional about the things you do. I like that.
I’m usually an early sleeper. I’m not the friend one should expect to stay up late at night with to binge on movies. Nope, I’ll sleep through the action. I however fell into a bad habit of going to bed late due to late work schedules and trying to balance many other stuff I was involved in. I did that habitually and would still rise early. The summary of that story is that my body eventually crashed. I then I struggled to sleep in general. Had to stop, do a total restructure of my activities and for a while my body clock was just out of rhythm. Now I’m more intentional about what I do and the time I do them. Lol! Like you, my body starts shutting down around 10 p.m. and I consistently wake at a particular time. It feels good especially now that I know what it feels like to be “without lock”.
I rather keeping it locked. Lol