I find this to be true. I sleep in 90-minute sleep cycles. I time my morning alarm thus (adding 10-15 minutes for initial spindown). When I wake up, even if it

I find this to be true. I sleep in 90-minute sleep cycles. I time my morning alarm thus (adding 10-15 minutes for initial spindown). When I wake up, even if it's 4.5hrs, my brain is typically going a mile-a-minute. There's so much I want to accomplish, it's hard to be mindful and go back to sleep (so I rarely do, especially if it's 'only' 6hrs vs. the 7.5 I seem to need). I looked back at my sleep logs, and I've slept longer than 7.5 only a handful of times in 2020, and it's always correlated with several nights of 1.5, 3, or 4.5 hrs.