I expect there will be no new guidance on the 11th.
I expect that the existing version of the guidance (released without warning or notification on 27th July) will be updated frequently, and randomly, often late at night, in the weeks between 11th and the start of term.
I then expect schools to be working with very different versions of the guidance, unsuspectingly, because they will now know when it has been changed.
I anticipate that the end of august will see an announcement from boris about hopw great everyone being in school will be, promising / threatening at least 3 things that have never ben mentioned in the guidance and are impossible in practical term.
i then expect another version of the guidance 3 days later from the DfE, who will have tried to square the circle between existing guidance and what BJ has said, creating something even more inconsistent thereby.
I then expect schools to open, with mixed success. Those who have interpreted the guidance in a way that turns out to be 'successful' will be praised, and others who have quite at random interpreted it in another will be vilified for 'failing children'.
Schools will start cliosing again within a fortnight, and we may have a workable version of guidance for the rest of the year (blended learning with smaller classes) by half term.