It is very unlikely that refurbished units hit the distribution channels that soon after release of a device - at that time, there usually aren't even enough to satisfy all swaps for repair without resorting to new devices, Besides, repair/refurbs are usually handled by a different partner or at any rate at a different plant than the production and distribution, so that a mixup can hardly happen.

It is most likely a repackaging because the units got OS updated between initial packaging and shipping, or the devices got redirected to another market and were supplied with another PSU.