I think some cases have been shipped out of the chinese or american Hasbro warehouses by accident, because someone found Voyager Bulkhead about 2 months ago in California. Not surprising though, with hundreds of thousands of boxes of toys being held back for 4-5 months, warehouses storing that volume of stock is bound to get some cases mixed up as employees intentionally or accidently send wrong stock. I've worked in enough warehouses to know how easy it is to mix up plain brown boxes with just abbreviated product descriptions on the outside.
I think if there were multiple sightings across many states, then it would be different, but I think Hasbro US are still intending to have a national release of June so as not to upset retailers who would be stuck with movie stock during the current demand for ANimated toys (because of the cartoon).