So the codes are no secret and can be published / bandied around with abandon? So, logic says that potential terrorists/ hijackers will know all about it. They will now be looking out for this in particular and certainly wouldn't allow a hijacked pilot to set any such code on the aircraft transponder.
So by definition, any "rogue" codes appearing on radars will be mere mistakes, spuriously set codes by inattentive pilots, won't they?
There's absolutely no need to send live armed Typhoons supersonic over land to intercept them. MOD can relax and just get D&D to ask a passing helicopter to check out the "rogue" aircraft.
Think of the green benefits, we're into saving the planet bigstyle! Sorted. Thank goodness for the all-seeing knowledge base on the BBC and PPRuNe.
