Mike, generally folks don't like to wait for an overnight to check in AM, but if logic serves me, the longer you wait the better. However, having said that, there is the consideration that when an engine is warm, things will settle quicker, but, there will always be some oil tucked away somewhere. At any rate, either way will work. You're trying to differentiate between rather small quantities of lubricant. So check it in whatever fashion you are comfortable with. I suppose someone has done a white paper about this issue, but personally, I don't think it's really all that important. I would find something else to be compulsive about, like changing the oil every 3,000 miles.
1987 BMW 325