The Third Department explained when the four-month statute of limitations begins to run when the triggering event is a policy memorandum issued by an administrative agency:
…[B]oth the statute and case law make clear that the statute of limitations period for a CPLR article 78 proceeding begins to run when “the determination to be reviewed becomes final and binding upon the petitioner” (CPLR 217 [1]…). Such determination, in turn, “becomes ‘final and binding’ when two requirements are met: completeness (finality) of the determination and exhaustion of administrative remedies. First, the agency must have reached a definitive position on the issue that inflicts actual, concrete injury and second, the injury inflicted may not be . . . significantly ameliorated by further administrative action or by steps available to the complaining party” … . In the context of quasi-legislative determinations such as the one at issue here, actual notice of the challenged determination is not required in order to start the statute of limitations clock; rather, the statute of limitations begins to run once the administrative agency’s “definitive position on the issue [becomes] readily ascertainable” to the complaining party … . Matter of School Adm’rs Assn of NY State v New York State Department of Civ Serv, 2015 NY Slip Op 00676, 3rd Dept 1-29-15