Too old for accountancy
I started studying AAT when I was 28 and then went on to do ACCA. Definitely not too old.
You are not too old
I started AAT at the age of 29 and started my first accountancy job at the age of 30. I have since completed ACCA and CIOT exams. I work in public practice and have found no difficulties in getting a job (provided you are prepared to start at the bottom and work up). If you think accountancy is for you, then go for it. I love the work and I have never regretted my decision to leave my previous job in banking.