Generally, this sounds typical. One of the reasons your arraignment is so far in the future is because all of this takes time.
Your questions make sense but DMV is understaffed, underfunded, disorganized, inefficient, and very slow. It usually takes DMV a couple of weeks to schedule a hearing date; that hearing date is set about thirty days or more after that.
DMV typically sends out the "discovery" (evidence including report) just prior to that to-be-scheduled hearing date, so it will be a long time before you receive it.
As soon as your attorney gets it from either from the DMV or the Prosecutor, your attorney will likely send you a copy of everything.
In any event, your attorney will make sure to request that DMV stay/stop the suspension action so you may continue to drive pending the outcome of the hearing.
Then, your attorney intends to appear on your behalf at your scheduled Court arraignment, enter a not guilty plea, and continue the case for about a number of weeks at which time you do not have to appear.
Not much happens at that arraignment date except your attorney gets a new date thereby allowing him or her to request and conduct discovery in your criminal case. Under California Rules, your attorney is not even allowed to request discovery (evidence) from the Prosecutor until after the arraignment.
After that, your attorney will conclude his or her investigation in the criminal matter and meet with the prosecutor's office.
Are you looking to defend the DUI without an attorney or with the assistance of an attorney? Although a Defendant is entitled to at least a redacted copy of a police report, typically these are not easy to obtain. You are correct that the DMV will have copies of your BAC as well as the DA’s office. Have you scheduled your DMV hearing yet? Understand you only have 10 days from the date of the incident to schedule one. You can try to contact the DMV, police department, or even the DA’s office; however I would not be surprised if they do not give you a copy of the police report and BAC results until after your arraignment.