—Orders, Supreme Court, New York County (Phyllis Gangel-Jacob, J.), both entered on or about September 30, 1998, dismissing the complaints, unanimously reversed, on the law, without costs', the plenary action converted to a CPLR article 78 proceeding, and the matter remanded for further proceedings.
Although pleaded as an action sounding in breach of contract to require the municipal respondent to adjust plaintiffs’ salaries, the relief actually being sought is to compel respondent to discharge a duty in conformity with its personnel policies and procedures. As such, plaintiffs must invoke the procedural requirements of article 78. When the administrative determination is deemed final for purposes of commencement of the four-month Statute of Limitations turns on whether the action sounds in mandamus or certiorari (see, Matter of Hamptons Hosp. Med. Ctr. v Moore, 52 NY2d 88, 96). In a proceeding for mandamus relief, it is necessary to make a *342demand and await a refusal, and the limitations period does not commence until the refusal (Matter of Bernstein v Industrial Commr. of State of N. Y., 57 AD2d 767). As an affirmative defense, the Statute of Limitations must be pleaded and proved (CPLR 3018 [b]; 3211 [a] [5]; see, Siegel, NY Prac § 34, at 40 [3d ed]). Plaintiffs’ demands were not formally rejected (see, Matter of Bates v County of Steuben, 113 Misc 2d 68). Rather, at various times, administrative personnel even tried to achieve the results sought by plaintiffs, well after the January 1993 date identified by the motion court as the time when the limitations period commenced. Moreover, respondent itself failed to prove the date when agency action was final. As such, the finality necessary to commence the limitations period has not been established, and the controversy remains viable. Accordingly, we convert this matter into an article 78 proceeding and remand for determination thereof. Concur — Sullivan, P. J., Nardelli, Mazzarelli, Tom and Friedman, JJ.