Once you have been indicted, you usually are more or less required to be brought up for your charges (whether it be additional preliminary hearings or simply to file your plea).  At the end of the day, your time frames are all based on the federal constitution, in that you have a right to a speedy trial.  Therefore, you must ensure that you are not simply being held in jail awaiting the next step.  In Mississippi, grand jury witnesses and those parties involved in the grand jury proceedings (who approve or deny an indictment) must keep the proceedings secret for at least six months, so that may also tell you whether your proceedings will last longer simply based on the confidentiality statutes regarding indictments alone.