California Civil Code 2924 is designed to protect you.

The Notice of Trustees Sale should be recorded with the County Recorder. This Notice of Trustees Sale indicates the date and site of the public sale. The California mortgage loan property foreclosure laws also require that a copy of the “Notice of Trustees Sale” is printed in a newspaper with a general circulation.”
Search this and make sure it was done.  Its easy.

The California home loan property foreclosure laws require that a duplicate of the Notice of Trustee Sale is SERVED to the residence owner who is subject to property foreclosure, AND a duplicate is also posted onto the home, usually on the front door or front gate.

Most of the time they DO NOT SERVE THE BORROWER. You MAY BE ABLE TO GET THEM on this one and stop the sale long enough to get your short sale completed in many cases.  Remember, a short sale is all parties best interest most of the time since 70% of the loans are guranteed by Fannie Mae and Freddie Mac, which is YOU THE AMERICAN TAXPAYER.

Under the California mortgage loan foreclosure laws, the house proprietor has until 5 days prior to the public sale to bring the loan current, although in reality, most lenders are prepared to operate with the property proprietor up until the day of the auction.
If you were not served properly than a court may agree with you that your rights were violated and therfore you were not afforded the protections as they were designed.

The Notice of Trustee Sale is a 20 day notification that on the 21st day they have the right to auction your property to the highest bidder, usually the bank.

If you were not served properly, than you lost your 15 additional days of redemption afforded you in California.

A trustee would much rather postpone than be wrong and have to pay.

NOT LEGAL ADVICE-JUST MY HUMBLE OPINION-SEEK INDIVIDUAL COUNSEL BASED ON YOUR OWN UNIQUE CIRCUMSTANCES