These preliminary court dates can be confusing but they are hugely procedural and should not cause you any concern.
If you are the defendant, your attorney should keep you updated on what is going on. If you are NOT the defendant, but perhaps a witness or victim, the prosecutor's office should keep you updated on what is going on. Even if you are not involved with the case, the facts are public record. You stated you have been utilizing the internet to stay current, you could also contact the clerk of court or the prosecutor, if you get a helpful person on the phone, they would likely be happy to assist you. To help ease your mind, this going back and forth with types of court appearances is completely normal.
If you watch any crime shows, you've probably heard the terms "NCIC/FCIC". This refers to a national criminal database and it is utilized by prosecutors all across the country. I am a former prosecutor and I used to get a background check on EVERY case that came in. As you might imagine, part of sentencing is the person's criminal history. I can assure you that the prosecutor has the defendant's complete criminal history.
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