Most of the most competitive commercial firms won't let you fill in the form if you don't have AAB (or is it ABB? I forget, probably depends).
For MC firms you need to appreciate that you are a very borderline candidate - Leciester is OK and your grades are probably just over the cut-off for some MC firms, but you won't find many Leciester grads at MC firms and you won't find many people with ABB (most will have AAA). You can still do it if thats what you want (remember that is a world of stuff other than MC firms and they are not for everyone, MC does not mean best), but you need to appreciate that you should aim for a first, really really prepare those applications and really get some great ECs if you want to stand a chance if that is a route you want to go down.