Legal Question in Real Estate Law in California

Sounds as though you were a subtenant, that is, a tenant of a tenant. Your rights to be in the place as a tenant flow through the main tenant, and if he loses his rights through being evicted, so do you. I suggest you immediately contact the landlord or property management company and see if it will make a deal with you, either to pay some rent and remain there a little longer while you look around, or maybe it'll give you a lease and you can then become the main tenant and stay on as such. Landlords don't like vacancies, they want steady rent and if you can show them you'd be a good tenant, they's have little motivation to toss you out.