No, it says work done since schools closed won't be counted.
Have a good look at the government advice to schools and teachers.
It's really important students can now relax and know that judgements will be made and are out of their control at this point.
Since schools finished, some schools have set lots of work and some none - no-one will be disadvantaged and the teacher judgement will be based on their knowledge of students across the course and what they would expect them to get if they sat the final exam.
Remember, teachers know that many students see uplift before now and the usual May exams - because they have school input and revise hard. The grades which will be input will be expected final grade if sitting the exam - not the grade on one recent essay or assessment - those final exam grades take everything into account and the gov website suggests lots of things teachers should consider such as (and it doesn't matter if any school/subject doesn't have all of them) like boo work, homework, assessments, mock exams, NEA if it exists, etc etc - anything that builds the picture.
Schools will be keen to have their students achieve as well as possible - rest assured that no-one will be 'doing them down' but the rank order is to ensure schools can't be overly generous and that if the statistical models suggest X amount from Y school should get a grade A* in Chemistry, it will be X amount who get it and if the school has suggested more than X amount, it will be the highest ranked (once prior attainment and school previous performance) has been taken into account.
It is unlikely schools will see lower results for their overall cohort than previously as the gov will have to be a little bit generous. Unless this cohort have substantially worse GCSEs than previous years in the school, results will follow a similar pattern - so similar %s of students getting each grade in each subject. As always,with exams too, schools with excellent attainment year on year, and students with excellent prior attainment at GCSE will do better - that's what happens in exams too. The teacher will have a chance to reflect where an individual student has outperformed what their GCSEs might have indicated (or underperfomred) but across whole cohorts each year, it is possible to project forward with some degree of accuracy from prior attainment.
Universities always take students who did not quite meet their offer. They will do so again.