回複：在灣區租的房子，一年合同將滿，

Your lease is legaly tenancy for years or fixed term tenancy. It terminates at its expiracy date. There is no legal requirement that the landlord shall give you a notice to vacate.

Your paying a montly rent will be construed, by most courts, as a convenience to you, not a proof of periodic tenancy, which does entitle you for an advance notice, normally equal to the length of the period, for a maximum of six months.

The landlord did not do anything wrong.

If you want to stay, there are two options. First, re-negotiate with the landlord for another lease. Second, ignore the notice and stay even after the expiracy of the lease, but still pay rent at your regular schedule. At that point, you become a tenancy at sufferance and the landlord has two option. If he accepts the rent, you would be a periodic tenant so that if the landlord tries to boot you off the land next time, he must give you notice. The landlord, of course, can treat you as a trespasser and file a claim to evict you.

There is also a small possibility that you stay, not payin rent and the landlord does not care, in which case you effectively start adverse possession. One out of a million chance.

In summary, just find another place and move.