5.1 APPLICABILITY. This By-law shall not apply to structures or uses
5.1 APPLICABILITY. This By-law shall not apply to structures or uses lawfully in existence or lawfully begun, or to a building or special permit issued before the first publication of notice of the public hearing required by G.L. c. 40A, s. 5 at which this By-law, or any relevant part thereof, was adopted. Such prior, lawfully existing non- conforming uses and structures may continue, provided that no modification of the use or structure is accomplished, unless authorized hereunder.