"You are carefully to avoid every act which would needlessly tend to provoke aggression; and f9r that reason you are not, without evident and imminent necessity, to take up any position which could be construed into the assumption of a hostile attitude. But you are to hold possession of the forts in this harbor, and if attacked you are to defend yourself to the last extremity. The smallness of yonr force will not permit you, perhaps, to occupy more than one of the three forts, but an attack on or attempt to take possession of either one of them will be regarded as an act of hostility, and you may then put your command into either of them which you may deem most proper to increase its power of resistance. You are also authorized to take similar defensive steps whenever you have tangible evidence of a design to proceed to a hostile act."
David, Seems to me that he did just what the order said. Thought he was in danger and moved to the safest place to protect his command as best he could.
Here is one you might like to read to understand what Anderson did. www.civilwarhome.com/CMHsumter.htm
Frank