My map subscription is expired .. it’d be unusual for a moa to be that close ,, 11 north of a city center? More likely on a low level military air route ,, there’s a Charleston Executive that has military and civilian users south of the city... looks like an old WW2 Navy training or submarine watching airport by the runway layout. KCHS is 9 NW of the city ,,, 9+3=12 ,, F16 could have been busy with landing prep if that was his destination...
I wrote without looking at a map. Sorry. Your analysis sounds about right. Thanks.