Stock for the Xbox one and PS4 has been awful up in my area...
I managed to get one from my local Argos after reserving it online (well, my wife reserved it for me)
Turns out they got 2 in stock on the same day, and both sold within hours.
I seem to be in Xbox one territory. I don't know anyone who owns a PS4, but there is zero stock anywhere
I can only speak for Asda (no doubt other retailers are similar), but stock was largely being prioritised to down South and the larger Scottish stores before filtering through to the smaller ones. Think it took a week or two for my store to get a few PS4s, and then another week or two for Xbox Ones to arrive. Not sure what availability has been like since, I'll find out when I'l back at work this weekend.
Ultimately it's the retailer that decides where the stock goes though.