N.Y. County Law § 843
In Suffolk county the county treasurer shall advance to the several school districts within said county, in anticipation of the collection of the school tax levies therein, and to provide funds for meeting the expenses in the said several districts prior to the receiving of moneys from the collection of school taxes, from funds in his hands available, such advancements only to be made upon a verified copy of the annual budget voted at the preceding school meeting and verified report of the trustees or board of education of each district applying for such advancement showing the amount of moneys on hand and a list of unpaid current bills of said district, such advancements to be made in installments in the months of September, October, November and December, and not exceeding fifteen per centum in September, fifteen per centum in October, ten per centum in November, and ten per centum in December, of the total amount of the annual budget of such district to which such advancement be made. The county treasurer of Suffolk county is hereby authorized to reimburse the county of Suffolk for such advancements as soon as the funds collected in the various school districts are available therefor.
N.Y. CountyLaw § 843