Do they care about exenuating circumstances?

I'll be applying for UK 2012 SA's this fall, but have quite poor A-level grades (end of high school exams, looked at for UK application). I'm just on/under the required grades depending on which BB, but quite a bit under what most applicants will have.

I do have a really good reason why - i was very ill and in a clinic for my final year (the year we take A-levels) and had to teach myself everything for that year in about 6 weeks. I still got into a semi-target uni because they were aware of my circumstances and am on track for a first (~3.7-4.0 GPA).

I've tried to make up for my results with EC's/Work exp; interning at a hedge fund this summer, running my own business at uni, having a small portfolio of stocks, founding/chairing a society etc.

I know how brutal they are with screening CV's in the initial stages due to the volume - will they take my circumstances into account or will it just be easier to bin my app? Or could it work to my favour in any way eg. diversity and blah?