As HB anorak says, there is no non dep deduction until the relevant person reached 18 so on “passported” awards, the imposition of any deduction is simply wrong
With other awards, if the person leaves education, this will result in a reduction in the applicable amount, not the the making of a non dependant deduction
Of itself, receipt or otherwise of child benefit is not the issue, the issue is whether or not the person is a qualifying person for child benefit purposes. This was explained by Judge Turnbull in CH/2812/2008 at [10-11]
10. Whether it was right to cease including a personal allowance in respect of Vanita in the Claimant’s applicable amount did not depend directly on whether child benefit had ceased, but on whether she had ceased to be a “young person”: see para. 2 of Part I to Schedule 3 to the Housing Benefit Regulations 2006. “Young person” is defined, in reg. 19(1) of those Regulations, as having the same meaning as “qualifying young person” in s.142 of the 1992 Act – i.e. the definition is effectively the same as that which applies in respect of child benefit.
11. Because Vanita’s new course was not (as I find) “advanced education”, within the definition in reg. 1(3) of the Child Benefit (General) Regulations 2006, the Council was wrong to remove the personal allowance in respect of Vanita, from which it follows that there was no overpayment, and therefore no recoverable overpayment. The entitlement to have a personal allowance in respect of Vanita included in the Claimant’s “applicable amount” turned on whether Vanita was still a “young person”, and not on whether child benefit was still in payment. If, as appears to have been the case, payment of child was wrongly terminated by the Revenue, it did not follow that the Council was entitled to cease treating Vanita as a “young person.”