As someone who has had a ton of sleep issues over the years this seems like the best advice here, although I would not increase past 8 hours and a regular 7 hou

As someone who has had a ton of sleep issues over the years this seems like the best advice here, although I would not increase past 8 hours and a regular 7 hours is likely to be fine for most people. Sleep apnea and circadian issues are common and worth considering, but there is a lot of individual variation in sleep so ultimately what feels best to you is likely what is best for you (other than that <6 hours of sleep is not a good idea). Sleeping much longer than usual may trigger circadian issues so it is worth being careful. In my experience it takes years for circadian changes to stabilize, at least once they are sufficiently disrupted (I have Non-24 and have been able to stop shifting my sleep for over a year at a time but eventually it comes back). At the same time, it seems to me that catching up on sleep is only really possible to a limited extent and only for a couple of days after sleep deprevation no matter how long the deprevation. Getting sufficient sleep for a while after sleep deprevation does seem to help reduce the effects of future deprevation, but I don't think getting extra sleep really helps. Keeping a stable circadian rhythm with suffient sleep is most important. I suspect that if not something like apnea that 10-12 hour sleep might be due to how sleep is maintained. There is a sleep or awake switch in the brain and also a "maintain the current state" network. To make the shift to awake cleanly, the "maintain current state" system is likely stronger in the morning (on a circadian rhythm, not just "after you wake up") but if you manage to be sleeping at the time it kicks in more strongly it may keep you asleep for hours even without any particular need to be asleep. This isn't necessarily what is actually happening but I think it fits the evidence. I don't think longer sleep is always worse than the alternative, however I suspect if it feels necessary then it is a sign of a more serious sleep issue and if it doesn't feel necessary then aiming for a regular circadian rhythm with sufficient sleep is a better option.