As you rightly say, the SDO is the rep for Harry during out of hours times and the "Flag waiving" signifies the start and end of the normal working day. Therefore by definition it should be the first and last duty of OC Bogs and Drains, and not the preserve of the chap(ess) who is trying to plan/get something useful out of the debrief.
See, the rules do work in our favour sometimes. Now, who's going to start the petition?
CBA