There is a concept of 'normal' and if your sleep cycle is so far out of 'normal' that it interferes with your ability to do 'normal' things, then it is your res

There is a concept of 'normal' and if your sleep cycle is so far out of 'normal' that it interferes with your ability to do 'normal' things, then it is your responsibility to determine if that will be a problem before you accept the job, not the employers. Even in the case of trading that you brought up, if starting at 6:30 is normal in that field, then the employer shouldn't need to bring up in the offer that they expect you to start at 6:30. If the employee is moving to a new field or to a place that has a different corporate culture, it should be their responsibility to find out what 'normal' is.