If you are a month to month tenant, either party--the landlord or the tenant may terminate the tenancy on a month's notice. Because the landlord may simply terminate the tenancy, it may also change its terms or conditions, such as making it a week to week tenancy or raising the rent, also on one month's notice. The landlord may not make this change retroactively, but as long as it provides the proper notice, it may do it in the future, going forward. So the landlord may not be able to do what it proposes immediately; but it would likely be able to do this in a month, after first giving you notice of its intention to make this change. Generally speaking, month to month tenants have relatively little protection.