SMI discounts and lCW/LCWRA

Im looking at an SMI council tax discount for a service user. He doesnt get PIP (and due to the nature of his illness will struggle to get this). He does however, have a brain lnjury.  He has just had a WCA and was given LCW (possibly will be challenged).

Looking at the council tax (discount disregards) regulations 1992, it is stated that in order to receive a discount, a person may be disregarded if entitled to one of the qualifying benefits listed - UC being one of them:

universal credit under Part 1 of the Welfare Reform Act the calculation of which includes an amount under regulation 27(1) of the Universal Credit Regulations 2013 in respect of the fact that the person in question has limited capability for work or limited capability for work and work-related activity or would include such an amount but for regulation 27(4) or 29(4) of those Regulations.

so to clarify, a claimant must actually receive an element in the calculation for LCW (which of course isnt possible for newer claimants) - an actual assessment showing LCW wont suffice?  im assuming that the reference to LCW is for those first claiming pre 2017?