Accountancy School Leavers AAT - Am I too old

I have a background in IT and also have run my own business. Unfortunately, I have had to close my business due to poor market conditions. I am seeking a career change in accountancy. I do not have a bachelors degree.
I am therefore looking at applying to school leavers position at the major accountancy firms. The issue is that I am 47 years old. I am too old to go to University and I only got BBB in my A-Levels. I don't meet the grade requirements for Liverpool or Manchester for Economics or Accounting & Finance.
Am I far too old to be considered for the school leavers programme? I have purchased the AAT materials from Kaplan in preparation but I'm wondering if this is a viable option.