These Regulations amend various instruments that govern the entitlement of a claimant (“C”), who has reached state pension credit qualifying age (“the qualifying age”), to universal credit (“UC”), state pension credit (“SPC”) and housing benefit for pensioners (“HB”), so as to provide for a smooth transition between those benefits where a person reaches that age, becomes part of a mixed-age couple, or certain other changes of circumstance occur. See section 1(6) of the State Pension Credit Act 2002 (c. 16) for the definition of “the qualifying age”. “Mixed-age”, in relation to a couple or a marriage, means where one member has attained the qualifying age and the other has not (see regulation 2(2)(b) which amends regulation 5 of the State Pension Credit Regulations 2002 (S.I. 2002/1792) (“the 2002 Regulations”) to insert that definition).