Again this link is just to show if they have stock for Sunday not for you to actually buy it and pick it up today as it says. I'm not entirely sure of the accuracy of the tracker so if you want to be certain just call a Best Buy.
It's very easy to check if they are holding stock for Sunday.
PS4 stock locator
If it shows "available" or "in-store only" it's available
If it shows "unavailable" then they don't have stock.
The store pickup page does have a "add to cart" if in stock but it won't let you actually add it as its disabled.
They will have Xbox Ones as well. I was only interested in the PS4 and didn't realize they'll have both at first
Lock and make me buy extended warranties and a gamer club subscription if old