Under Georgia law, OCGA Sec. 44-7-7, when a tenant occupies property as a tenant at will, in order to terminate the tenancy a landlord must give sixty days notice, and a tenant must give thirty days notice.

It is possible that the lease includes a provision that allows the landlord to give notice to the tenant if the property is sold, then the landlord may be able to give notice based upon the transfer -- whether the provision would apply for a sale to a co-owner will depend upon the language of the lease, if in fact there is such a clause -- but I see no authority by which the landlord can shorten the statutory notice period even if the tenancy is arguably week-to-week.