Jobseekers Allowance Arrears

Hi,
I have been out of work since April 2009. I only applied for jobseekers allowance in Feb 2010. I was successful in my application and just received my first payment which was backdated to the Feb 2010 date when I applied.
The reason why I never applied after April 2009 was that I presumed an individual working for their own limited company could not apply for this.
As this was now not the case can I now expect to receive arrears from May 2009 to Jan 2010?

The form I received states "We will issue any arrears not included in your first payment shortly"

What happens if I get a job in the meantime,if I am entitled to the arrears do I still get them?

You won't automatically get arrears, your claim starts when you make it.

You would need to put in writing to them why you thought you weren't entitled and therefore didn't apply at the time. Then the Deciding Officer will consider it, and may backdate the claim at their discression