I was wondering the same thing. I hope you get a reply. I also ordered these...(from Barney's in US 10/UK 40) I'm usually around a 9.5-10 and really hoping these fit.
I ordered both sizes the 9 and the 10 and the 10 is a little big but I'm worried they will get bigger once they begin to stretch. The 9 is a little tight but not unbearable so I'm going to wear a few pairs of thick socks to see if they loosen up before I one pair goes back. If you're a 9.5 the US 10 should fit fine!!