This is one circumstance where you do not notify the NCS of a change in your status. This deserves a little explaination. This would normally occur only if there is a presence of explosives or explosive chemicals or vapors, and there is the possibility that a spark producing electronic device is present which might be triggered by an RF Signal. An NCS operator is under high stress. Typically, there is a whole lot going on at an NCS that the field operators never know about.
Hams are patriotic, independent people and they are volunteers.
That's absolutely correct. We don't have to take orders. The NCS will tell you if anything else is needed. You have turned the location over to another operator You will normally not need to tell NCS that you are leaving. However if there are specific instructions from NCS then follow those instructions.