20. Where the claimant occupies a dwelling as the claimant's home and the dwelling is also occupied by another person and there is a contractual liability to make payments to the claimant in respect of the occupation of the dwelling by that person or a member of that person's family—E+W+S
(a)where the aggregate of any payments made in respect of any one week in respect of the occupation of the dwelling by that person or a member of that person's family, or by that person and a member of that person's family, is less than £20, the whole of that amount; or
(b)where the aggregate of such payments is £20 or more per week, £20.