It's not good that you're unable to get in touch with your attorney. A pre-trial date is not likely to be continued because of a lack of communication between you and your attorney. You will have an opportunity to talk to your attorney in court before any decisions are made.
Whether your will be allowed to adjourn your pretrial is up to the judge assigned to your case. Some jurisdictions are very reluctant to adjourn anything while others are much more lenient in that respect. In some courts it is the court administrator that makes that decision. If you feel that your attorney is unprepared, you should talk with him or her about that issue the minute that you see him/her at the pretrial. Oftentimes, it doesn't take more than a few minutes of file review to be ready to conduct a pretrial.
Unusual for an attorney not to at least have an answering maching. Usually, the attorney will have obtained a copy of any police report, read it, and be prepared to meet you before or at pre-trial. It seems a weak basis for rescheduling, especially when, as my colleague notes, it make not take much time to prepare for this initial phase. It is not clear from your post where things stand as to misdemeanor or felony, how much time is still available, and how complex the case might be. If there is time, write to your attorney, or leave another telephone message.
We do not have a client/attorney relationship until you make an appointment, we discuss your case face to face, I accept a retainer, and we explictly agree to enter into representation.
Some attorneys will not talk to their clients until the Pretrial conference. Although this is not my practice, your attorney probably wants to see what kind of plea deal he or she can get you before discussing your case with you fully. It does not mean your attorney is unprepared. Have faith in your attorney at least until the Pretrial is over. If you decide you you would like to hire a different attorney you have a right to do so.
Kennedy Law Office, PLLC
Disclaimer: No attorney-client relationship has been established. Please contact an attorney about your legal rights. This answer is for educational purposes only.