California Code, Civil Code - CIV § 1991

Where a notice of belief of abandonment is given to a lessee pursuant to Section 1951.3, the notice to the former tenant given pursuant to Section 1983 may, but need not, be given at the same time as the notice of belief of abandonment even though the tenancy is not terminated until the end of the period specified in the notice of belief of abandonment. If the notices are so given, the notices may, but need not, be combined in one notice that contains all the information required by the sections under which the notices are given.