Gotcha, that wasn't clear in your earlier comment.
If someone is unable to get adequate sleep on a 24-hour day due to their circadian rhythm misalignment then I believe this is non-24 even if it's because they wake up too early rather then go to sleep too late when trying to keep 24-hour days.
If someone is unable to get adequate sleep on a 24-hour day due to their circadian rhythm misalignment then I believe this is non-24 even if it's because they wake up too early rather then go to sleep too late when trying to keep 24-hour days.