If you are not a full service area and they don't meet the gateway conditions, he can ask you to terminate his award and that request will amount to a change of circumstances that will enable you to end his award (CJSA/3979/1999,CDLA/1589/2005 )
The claim by the partner will need to be made in the same week that the (former) claimant asks for the award to be withdrawn, otherwise there will be a gap in entitlement of at least a week (CH/2008/2011 distinguished)
Temporary absence from the dwellling for the purposes of Regulation 7 is not the same thing as membership of the household for the purposes of Regulation 21 (CIS/671/1992)
I don't see the need to swap claimants when he comes back unless certain premiums such as the disability premium could be at issue
