N.Y. Comp. Codes R. & Regs. tit. 9 § 465.4 : EXECUTIVE DEPARTMENT — Division of Human Rights — Rules Of Practice — Amendments to complaint

(a) Power to amend. The division or the complainant shall have the power reasonably and fairly to amend the complaint. No party may be removed by any amendment. After a hearing is commenced before an administrative law judge, any amendment is subject to the discretion of the administrative law judge.
(b) Complainant's power. The complainant has the right to amend the complaint in a reasonable manner before the commencement of a hearing.
(c) Division's power. The regional director, division attorney, or administrative law judge may reasonably amend the complaint.
(d) Any amendments made after a probable cause determination are not subject to any further investigations or determinations of probable cause.
(e) Service.
(1) Any amendment to a complaint shall be served upon all parties unless made upon the record at a public hearing before an administrative law judge. If an amendment adds new parties, a copy of the notice of hearing must be served upon such parties.
(2) When a complaint is amended after an answer has been filed but before the hearing, each respondent who has filed an answer shall be allowed to file an amended answer with the division attorney at least two business days prior to the hearing.

N.Y. Comp. Codes R. & Regs. Tit. 9 § 465.4