I know its not a huge biggy currently but the competition (non FTTP) are catching up where upstream bandwith is concerned.... and thats pretty much all that Openreach's network has over the alternative superfast ISP.
Competing with Virgin Media on speeds has never been a big deal for Openreach and isn't going to start now. They've accepted that, short of a massive FTTP splurge, they can't keep up.
VM are actually ahead on upstream bandwidth now, too, by the way. The Homeworks 300 package, alongside 320Mb downstream, delivers a clean >20Mb upstream after overheads, the Openreach 76Mb FTTC does not.