The foreclosure process is controlled by state laws & the lenders have no choice but to follow these laws when foreclosing on you.
You may wish to review these laws, and they probably are posted on your state's website.
In my state, once the foreclosure sale has taken place, the new owner must evict you. The first eviction notice is voluntary, & is basically meaningless. The 2nd eviction notice is from the court. When someone gets this 2nd notice, they can apply to the court for a hearing on the eviction. At the hearing, the judges will typically give people an additional 30 days to move out.
I would suggest that you look at the eviction notice to see if it has the name of a court. If no court, it is probably just a preliminary notice. If the notice has the name of the court, contact the court clerk for an application for a hearing.
Hope this perspective helps & good luck!
The process is probably similar in California
If your home was sold at a foreclosure auction, then you can expect a notice from the purchasing party. This is usually done through an agent (usually attorney or broker). It is common for the agent to have the authority to grant moving expenses. This is commonly referred to as the "cash for keys" program.
Another option would be to seek an injunction and filing a complaint against your lender.
On a side note, filing bankruptcy would afford you an automatic stay; temporarily suspending any collection or eviction efforts.
Hope this helps!