Seems to me that people forget that nursing is a 24 hour job. 1830 would be the best time to sign off your orders for the 12 hours you worked that is how I have always had my nurses do it. It makes the most sense because you are trying to wrap things up and complete you tasks to be prepared to give an accurate report. Again nursing is a 24 hour job, unless it is stat, and always communicate with your physicians to understand why it is stat, they do tend to wright stat just to make sure its done today and not tommorow.