Entitled to JSA at this late stage??

I left work at the very end of 2011, and for various reasons have not been actively looking for a job so did not claim JSA (Contributions based).

I believe that I will not be entitled if I try to claim in 2013 (my OH is working, so Income based would be out).

My question is: my circumstances have now changed, so if I start to claim this month, am I only entitled to JSA for the remainder of December, or would the six months start from then? Hope someone can help.