No matter what
“If we say your package will arrive on December 2nd, then it will arrive on December 2nd – even if we have to ship it back and forth for a couple days.”
This seems to be FedEx’s philosophy, anyway…
I expect my package to arrive tomorrow at 7pm sharp, even if the driver needs to circle around the block a few times.
UPS has the same philosophy…they once routed a package through Canada just to be right.