working age hb couple reach pension age after 15.05.19

HI thanks for all your input , I haven’t spoke to my colleague who is still on leave. To clarify any changes to HB should have applied the change of circumstances the following Monday ( 9th ) and not the SDP during the week. That being said ,  it is still the case that the SDP could have been applied on the Monday by virtue of being captured by the superseding decision. HB Anorak have you got a link/copy of the UT decision you refer to ?
Once again many thanks for everybody’s contribution.