Register for articleship- now or later

Hi friends.. 

i will have to get myself registered for articleship till 31st oct 2012. i've passed ipcc 1st group. The firms where i went 4 my interview want me 2 complete my 2nd group nd then apply (they are renowned firms of our locality). Bt my CA final attempt will get postponed to nov 2015 then.

So should i get registered with a small firm for the time being nd then switch to the firms i've mentioned above  ( the risk is that the small firm might not allow me to leave ) 

OR

first clear my group 2 ( bt the big firms have not promised me )

Pls help me out