At least 10 days before the first public hearing held by the Town Board on an application or motion to amend the Zoning Map, subject to this section, the Town shall cause a six-foot-square sign to be erected on the affected property, facing the nearest street, at a distance of no more than 10 feet from the front line, bearing the following words: "Commercial Zoning Application Pending," together with the telephone number of the Town of Boston to be used for additional information. The sign shall remain posted during the pendency of the application to the conclusion thereof by vote of the Town Board or, as the case may be, by any earlier termination of the proposal.