I honestly don't know. I do know the Shiny Entei I have has a July date, and I received it (at Lv.100 to boot) in July. It had me questioning legitimacy, too. For all we know, perhaps it doesn't change.
I oughta check on a couple of transfers from yesterday and see. I'll have more to test with, too...and now that I think of it, my Shiny Nincada is a perfect one to check...
I oughta check on a couple of transfers from yesterday and see. I'll have more to test with, too...and now that I think of it, my Shiny Nincada is a perfect one to check...