get_holiday_ship_by_dates
Holiday ship-by dates
Use when someone asks for the last day to ship a gift so it arrives before Christmas, or how many days are left. Returns USPS's published 2026 holiday ship-by dates for the lower 48 states by mail service, with the USPS source and the date we last checked. Each result includes the note "Carrier published dates, not a guarantee. Order a few days earlier, and earlier still for logo items." For UPS and FedEx, it says to check the carrier's own schedule for the route.
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