New Delhi: The Election Commission has asked its state election officers to be ready for the SIR by September 30, in an indication that the poll authority could launch the voter list cleanup exercise as early as October-November. Several state CEOs have already put up the voter lists published after their last SIR on their websites. The website of the Delhi CEO has the voter list from 2008, when the last intensive revision took place in the national capital. In Uttarakhand, the last SIR took place in 2006 and the electoral roll from that year is now on the state CEO's website. The primary aim of the intensive revision is to weed out foreign illegal migrants by checking their place of birth.