Hello
@cuccuttroisong Sorry for the late response but I also paid with PayPal and was charged right away for the pro as well. I logged into B&H and went to my order then selected the chat option to reach customer service. I told them that I didn't want to wait until February and if it was possible to swap my order to the air.
Within a minute I got the email showing the new order for the air and a refund for the price difference.
So yes, they will literally swap the items right on the spot for you. You don't have to cancel and reorder.
I'm writing this from the M1Air right now actually. Very nice.