Extenuating circumstances

Would my current situation qualify as an extenuating circumstance?
Recently my school has gone downhill, and the majority of teachers are leaving. I've just found out that next year, 5 out of 7 of my current teachers will be leaving the school, and the school haven't been able to find any new teachers for Further Maths. I've been told we are going to have to take the entire subject by ourselves, online, which I'm struggling to imagine being feasible. If we do get any lessons (which I've been told is unlikely), they will be delivered by someone who isn't qualified in Further Maths.
I aim to apply to Cambridge to study maths, and although my predicted grades are fine, would it be worth filling out an extenuating circumstances form to let them know of the position I will be in?

YES.
Make sure that your school mentions this in your UCAS reference.
And check the 'extenuating/mitigating circumstances' process at each Uni you will be applying to - google and if you can't find it, email their admissions team and ask. There is usually a separate form that you / the school need to complete and then send direct to each Unis at the same time as you submit your UCAS application - example : Extenuating circumstances | Study at Bristol | University of Bristol