Legal Question in Criminal Law in California

The DA can add, drop of change charges at any time.

If you don't know how to represent yourself effectively against an experienced prosecutor intending to convict, then hire an attorney who does, who will try to get a dismissal, charge reduction, diversion, program, or other decent outcome through motions, plea bargain, or take it to trial if appropriate. If serious about hiring counsel to help in this, and if the charges are in SoCal courts, feel free to contact me. I�ll be happy to help fight this and get the best outcome possible, using whatever defenses there may be.

Yes, but the criminal defendant has the right to be arraigned on the new charges. You mention a preliminary hearing, which is usually used in felony cases and rarely used in misdemeanor cases. There are special rules that govern these situations.

yes definitely ... subject to procedural rules, as mentioned above. Good luck!