2. How important are the arrival and departure times and dates we established?

They are important. You will tell us in advance as to when you expect to arrive so that our caretakers will be expecting you to arrive within that, say, two-hour window. They will escort you to the castle, give you the keys and show you around. It is important that you to arrive during daylight so you can arrive comfortably and be oriented to the castle-village and its grounds.

If you want to stay an extra day or so, that may be possible depending on availability.  If you do stay extra days, you will be charged at a pro rata amount.  If you want to leave early, there will be no refund. Of course, if others are scheduled to arrive shortly after you leave, extra time will not be available.