A proposed preliminary plan shall be submitted simultaneously with an application for mixed commercial district zoning. The preliminary plan shall specify the nature and character of the information, plans, and stipulations to be submitted as the final plan. The preliminary plan must be approved in conjunction with the zoning of an area as mixed commercial district. The preliminary plan shall be reviewed in accordance with the procedure specified in Chapter 15.52 of this title. The permitted intensity of use may be specified by upper and lower limits set by the city council. (Ord. 1984-20 § 1 (part): prior code § 5-2-4(Q)(3)(a))