I was told it’s around 122, but didn’t ask for more specific information. So maybe if your DD scores really much higher in some sections and gets a 120 in another, perhaps it is averaged out.
I realised afterwards that our lack of a tutor, being at a state school with zero guidance and not having been doing certain types of tests at home (Atom) probably meant my DD’s scores weren’t high enough. But we were very lucky to get into her favourite school, so in the end it doesn’t matter- just wasn’t a great experience!