§ 83-a. Exemption of lots shown on approved subdivision plats. 1.
Notwithstanding any inconsistent provision of this chapter or of any
general, special or local law, the provisions of a zoning ordinance or
local law hereafter adopted, or of a change or amendment thereto, which
provisions:

(a) establish or increase lot areas or lot dimensions which are in
excess of the areas or dimensions of the lots shown and delineated on a
residential subdivision plat which has been duly approved by the
planning board, or other board or officer vested with authority to
approve subdivision plats, if any, of the city in which the land shown
on said plat is situate and duly filed in the office of the recording
officer of the county in which the land shown on said subdivision plat
is situate; or

(b) establish or increase side, rear or front yard or set back
requirements in excess of those applicable to lots under the provision
of the zoning ordinance or local law, if any, in force and effect at the
time of the filing of the said duly approved residential subdivision
plat or first section thereof;

shall not, for the period of time prescribed in subdivision two of
this section, be applicable to or in any way affect any of the lots
shown and delineated on such subdivision plat.

2. If at the time of the filing of the subdivision plat or first
section thereof referred to in subdivision one of this section there was
in the city:

(a) both a zoning ordinance or local law and a planning board vested
with authority to approve subdivision plats, then the exemption provided
for in subdivision one of this section shall apply for a period of three
years after the filing of the approved subdivision plat or first section
thereof; or

(b) a zoning ordinance or local law in effect in the city but there
was no planning board in said city vested with authority to approve
subdivision plats, then the exemption provided for in subdivision one of
this section shall apply for a period of two years after the filing of
the approved subdivision plat or first section thereof; or

(c) no zoning ordinance or local law in the city but there was a
planning board vested with authority to approve subdivision plats, then
the exemption provided for in subdivision one of this section shall
apply for a period of two years after the filing of the approved
subdivision plat or first section thereof; or

(d) no zoning ordinance or local law in the city and no planning board
vested with authority to approve subdivision plats, then the exemption
provided for in subdivision one of this section shall apply for a period
of one year after the filing of the subdivision plat or first section
thereof.