Several months ago
I detailed, complete with graphs, how my internal clock had reset to Old Peoples Time over the last few years.
Couple more observations.
1. OPT is especially fine in a Spokane summer. When you get up at 3, you're starting at the coolest point of the day, and you've got a good eight hours with open windows and doors, letting Nature cool the house. Typically turn off the air conditioner at wakeup, turn it on at noon. When I was on YPT, I slept through the cool hours and had to run the AC constantly.
2. Getting everything done. The South Park episode
on the AARP invasion makes this point clearly: "They've tried to stop them, son, but the seniors get up so early in the morning they get everything done before everyone else is even awake!" When I first watched that episode I was still on YPT and thought it was a parodic exaggeration. Nope. It's wonderfully easy to get all the necessary stuff out of the way by 9. Wash, laundry, yard work, eat twice, dump, go to store. On YPT, most of those chores had to wait till evening when I was tired and hot, and too often the dump didn't happen at all. Ironically, I could probably do an 8-5 job much better now than before! Luckily, don't need to.
2a. Those pre-dawn hours always seem long no matter how you're approaching them. But the length has different implications
in YPT and OPT. When you're still trying to achieve sleep at 4 AM, those loooooong seconds are famously nightmarish. When you're in the middle of chores and play, those loooooong seconds are wonderful. More subjective time for chores and play!
3. OPT gives you a broader view of neighborhood activity. This neighborhood is never fully asleep. Half the neighbors within my visual range are OP, with lights coming on before 4 AM. Half are YP, with lights still on at 2 AM. There may be a brief interval when everything's dark, but it's not long or reliable. I suspect a contingent of snoopy OP, peering out of lighted windows at all hours, is a major ingredient of a safe neighborhood.