Hey Shara -- you're right in that deep sleep is more likely to occur earlier in the night when we are sleeping normally. REM sleep normally occurs more in the latter half of our sleep bout (in the morning). This doesn't necessarily accord with whether or not the sun is up in everyone - but it may well in you!
Remember to scroll down in the sleep page and look at your heart rate cycles -- their shape and consistency of cycle can correlate well with subjective sleep quality in my and my fiance's experience. Also go to the readiness page and scroll down to see your overnight HRV!
Also remember that the Oura ring isn't a perfect sleep-stage scorer by any means, so take their estimation with a grain of salt. This paper, "The Sleep of the Ring" is open source so you can read it - and compares oura to polysomnography (the ''gold standard'' for sleep staging where a trained technician looks over electrical brain and eye movement activity by hand -- or now a days, employs software to help them do so more efficiently). It's important to remember that this "gold standard" isn't perfect-- different technicians I believe will score things a little differently, though the exact number on % differences reported i don't know.
The study basically says that Oura is 1) quite good at detecting wake vs. sleep 2) overestimates rem and underestimates deep sleep a little. Below is a screenshot of a table from the paper showing discrepancies between Oura and the polysomnograph for the 41 people in the study.
I highly recommend reading through this to learn a little more about the performance of the device
As usual let me know if you have more questions and thank you for posting this here!