A public hearing shall be held by the Board of Appeals, and within
30 days of such hearing it shall report to the City Council any proposed
amendments. Notice of such hearing shall be given by publishing in
some newspaper of general circulation, not more than 30 days nor less
than 15 days before the hearing, stating the time and place of such
hearing. In case of written protest against any proposed amendment,
signed by the owners of 20% of the frontage immediately adjoining
or across the rear lot lines therefrom, or by the owners of 20% of
the frontage directly opposite the frontage proposed to be altered
as to such regulations or district and filed with the City Council,
such amendments shall not be passed except by the favorable vote of
2/3 of all the members of the City Council.