Considering the fact that Bandai America's headquarters is in Cypress, California, I'm not surprised that the state of California seems to be the first one with the V4.5 being sold. However, given the scant quantity of V4.5 on eBay, I have the feeling that either the seller bought those Tamagotchi in a store that wasn't supposed to put the V4.5 on the shelves yet, or that the eBay seller (Arroyo Books and Collectibles) perhaps got a shipment in early?
I think that it may've been a "leak" basically.