9 NYCRR § 2521.1 — Initial legal regulated rents for housing accommodations (Rent Stabilization Code, via Cornell LII)

(i) When an owner combines two or more rent
regulated apartments, the owner may use each of the previous apartments'
remaining individual apartment improvement allowances for the purposes of a
temporary individual apartment improvement rent increase. The owner shall
subsequently designate a surviving apartment for the purposes of registration
that has the same apartment number as one of the prior apartments. If that
prior apartment has any reimbursable individual apartment improvement money
remaining after the combination, that money may be reimbursed for future
individual apartment improvements undertaken within the subsequent fifteen
years following the combination.

(ii) In order for an owner to qualify for a
temporary individual apartment improvement rent increase when apartments are
combined, the requirements for an individual apartment improvement, including
all notification requirements under Section
of this
Title must be met.2522.4(a)

(7)
Owners shall maintain the records and rent histories of all combined
apartments, both prior to and post combination, for the purposes of rent
setting, overcharge and all other proceedings to which the records are
applicable.

(n) For
housing accommodations made subject to this Title as of June 14, 2019 as set
forth in 2520.11(f), (j) and (k) the initial rents thereafter upon vacatur of
the not for profit and affiliated subtenant shall be set using the rent in
effect for the stabilized tenant in occupancy immediately prior to occupancy by
the not for profit and the affiliated subtenant plus any applicable
increases.