Legal Question in Real Estate Law in California

I can't speak to special requirements in Los Angeles or any other community with a rent-control ordinance. Nevertheless, it might be useful (or perhaps it's only confusing) to point out that in most parts of the World, when a lease for X months or years, it expires, and no one needs to give any notices, or go through any process. The tenant simply moves out. If the tenant doesn't move out, it is immediately subject to unlawful detainer proceedings.

Sure, if the tenant doesn't move out, and tenders rent, and the landlord accepts the rent, the parties are presumed to have extended the lease on a periodic basis, usually month-to-month. This happens a lot, but it isn't automatic. It requires a failure to vacate, in which the erstwhile landlord acquiesces by accepting a tender of rent.

Rent-control areas may be different, but take this as the base line.