"1. Unlimited liability applies. The standard of unlimited liability applies if unauthorized transfers appear on a periodic statement, and may apply in conjunction with the first two tiers of liability. If a periodic statement shows an unauthorized transfer made with a lost or stolen debit card, the consumer must notify the financial institution within 60 calendar days after the periodic statement was sent; otherwise, the consumer faces unlimited liability for all unauthorized transfers made after the 60-day period. The consumer's liability for unauthorized transfers before the statement is sent, and up to 60 days following, is determined based on the first two tiers of liability: up to $50 if the consumer notifies the financial institution within two business days of learning of the loss or theft of the card and up to $500 if the consumer notifies the institution after two business days of learning of the loss or theft."
You have 30 days from receipt of your bank statement. It's in the audio interview of which this article is an exerpt.