Such regulations, restrictions and boundaries[1] may from time to time be amended, supplemented, changed, modified, or repealed.

When the owners of more than 50% of the frontage within a district or part of a district shall present to the Borough Council a duly signed petition for the amendment, change or modification of said district or part of a district, the Borough Council shall act upon said petition within 120 days after the filing of said petition with the Borough Clerk. Said petition shall be accompanied with a map showing the lots, buildings, and uses of property within the area for which the change of district is asked as well as of all of the property within 100 feet therefrom (exclusive of street space). Said petition shall, furthermore, set forth the grounds or reasons for the proposed change. Any proposed amendment or change of district or part of district petitioned by owners shall be referred to the Planning Commission for study and report. The Planning Commission shall report back to the Borough Council its findings upon such proposed amendment or change within 60 days after the receipt of such references.