On the first appearance date (listed on the ticket) for a california misdemeanor dui , my lawyer appeared. no charges had yet been filed by the DA.
AFTER the expiration of the statute of limitations, it turns out that an arraignment had been scheduled a month after the original hearing date, WITH A NEW CASE NUMBER.
Neither my lawyer nor I were notified of a new case number, or of the new date. When no one appeared, a bench warrant was issued.

My lawyer would periodically follow up with to DA (after we initially discussed checking with the court, so as not to 'remind' the DA to file).
On my last check-in with the lawyer, after discovering a public record on unicourt with an arraignment date I knew nothing about, my lawyer said when he followed up with the DA(???) to see if a case had been filed. The DA apologized(?) for giving inaccurate information ('nothing has been filed yet').

In asking my lawyer how there could have been a scheduled arraignment without he or I being notified, he stated
NEITHER THE COURT NOR DA NEED TO GIVE NOTICE OF THE COURT DATE???