I think these revelations make it difficult, if not impossible, for Boris Johnson to bring in restrictions on family gatherings for Christmas and New Year.
He would have to announce, barely a week before Christmas Day, that such gatherings are not allowed, and I think the vast majority of people would stick two fingers up at him and say:-
"...Up yours Boris, we're going ahead with our plans anyway, just what do you think you are going to do about it..?"
I think what is most likely to happen next week is that the current mask rules and money making scheme for the testing companies travel testing rules are extended for a further three weeks until the second week of January, together with perhaps advice about working from home over Christmas, which a lot of people do anyway.