This By-law may be amended from time to time at an annual or special Town Meeting in accordance with the provisions of Chapter 40A of the General Laws.

Except as otherwise provided in Chapter 40A of the General Laws, the adoption of this By-law shall not affect the validity of any action lawfully taken under the provision of the Zoning By-law in effect prior to the date this By-law becomes effective.

Nothing in this By-law shall be construed as establishing regulations or restrictions which are not uniform for each class or kind of buildings, structures or land, and for each class or kind of use in each district.

Nothing in this By-law shall prevent the restoration of a wall declared unsafe by the Building Commissioner, or the erection of iron fire escapes on any building in existence on June 24, 1922.

The invalidity of any section or provision of this By-law shall not render invalid any other section or provision of this By-law.

In the case of amendments to this By-law or changes in the district or their boundaries subsequent to the date this By-law becomes effective, the right to continue the use or maintenance of any building, structure or premises which was lawful when such amendment or change became effective shall not be impaired by any such amendment or change, except as provided in Chapter 40A of the General Laws. Amendments shall not adversely affect special permits and variances issued or granted by the Board of Appeals prior to the date of the first advertisement of the amendments, provided the work or action authorized under such special permits or variances shall commence within one year after the effective date of such an amendment and within six months of the issuance of the permit and thereafter shall proceed in good faith continuously to completion so far as is reasonably practicable under the circumstances. The Board of Appeals, upon written application and after due notice and a public hearing as provided by statute, may grant one or more extensions of time for periods not to exceed one year for each such extension. The date when each such amendment or change was made is shown by an appendix to this By-law on file in the office of the Town Clerk.