Please list all circumstances that can delay when the statute begins.
That's not really possible because, although there aren't many exceptions, the ones that exist tend to be very fact-specific. There is a decent summary of New York defamation law here: http://www.citmedialaw.org/legal-guide/new-york-defamation-law
The better alternative would be to consult with a competent attorney who has expertise in defamation to discuss the actual facts of your case in detail; that attorney will be able to give you the sort of answer we cannot.
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