Predicted Grades

Answered

Last year, all of UK and the Commonwealth was affected by COVID-19 so in lieu of actual test scores, school counselors were encouraged to send in predicted scores for their cohorts. As a result of this voluntary system, many students were given higher predictive scores on their A levels and many other students were auto-deducted and were very disappointed. So this is a very risky undertaking for any college-bound student because they don't know if they are going to be grade inflated or grade deflated on a predictive basis.

I would err on the side of caution if I were you because you already stated 2 important facts. 1.) None of the lecturers know you and 2.) You don't even know all of them. Therefore, no one is going to go out on a limb for you and say you a destined to get all A (stars) or all As. You are rolling the dice if you ask the 3 lecturers to submit predictive grades to Harvard.

I don't know if there are any A-level experts on CollegeVine so you should have a serious conversation first with your school counselor and your parents. Also, do some independent research about what I'm talking about.

https://blogs.lse.ac.uk/impactofsocialsciences/2020/08/26/fk-the-algorithm-what-the-world-can-learn-from-the-uks-a-level-grading-fiasco/

https://www.theguardian.com/education/2021/may/22/top-pupils-rejected-by-universities-in-a-levels-fiasco-fallout

https://en.wikipedia.org/wiki/2020_UK_GCSE_and_A-Level_grading_controversy

https://www.theguardian.com/education/2021/aug/10/a-level-entries-across-uk-awarded-top-grades