You can override certain SOM settings by setting a "settings" variable in a SOM (do this during the first 2 seconds of a mission!). In this Array you can send the SOM your custom pool of SecOps for this mission, you can disable the standard H.Q. radio communications, you can set different callsigns and set an initial delay (default is 30 seconds). If you do not want to set all settings, you may pass nil for those that you wish to leave on their default values. A typical settings Array can look like this:
private ["_pool", "_hq", "_callsigns", "initialDelay", "_autoReinforce", "_settings"];
_hq = false;
//Team text, team speech, H.Q. text, H.Q. speech.
_callsigns = ["Razor", ["Razor"], "Frostbite", ["Frostbite"]];
//Delay in seconds before starting random SecOps selection.
_initialDelay = 60;
//Should an automatic Reinforce be triggered when there are casualties?
//Default is true.
_autoReinforce = false;
_som setVariable ["settings", _settings];