Except as otherwise provided in Chapter 15.48 of this title, any sign which is located on property which becomes vacant and unoccupied for a period of three months or more, or any sign which was erected for an occupant or business unrelated to the present occupant or his or her business, or a sign which pertains to a time, event, or purpose which no longer applies, shall be deemed to have been abandoned. Permanent signs applicable to a business temporarily suspended because of a change of ownership or management of such business shall not be deemed abandoned unless the property remains vacant for a period of six months or more. An abandoned sign is prohibited and shall be promptly removed by the owner of the sign or owner of the premises. (Prior code § 3.09.171)