At present, one of the reasons for getting Income Support is that you are a lone parent with at least one child under 16. As soon as there are no children under 16, the lone parent has to claim Jobseekers Allowance.
The government proposes that this age is lowered to 12 in November 2008, 10 in Octobe 2009 and 7 by 2010. It may mean lone parents claim Employment and Support Allowance.