Big problems with mixed aged couples who get SDP

Hi

I have just spoken to someone from the benefits service about a problem with my ESA payments when my wife reaches state pension age in September.
I presently receive IR ESA support group rate. Both my wife and I get enhanced rate PIP for care and mobility..she is presently receiving Carers allowance for me and we receive SDP and disability income guarantee.
However, the calculation I received for after she receives her pension showed my ESA reducing by over £90 a week. This calculation showed the couples allowance, carer premium( as she keeps underlying entitlement), support group premium and now pensioner premium.
However, I have been awarded no disability premiums at all. Having first phoned on Monday and again today, I finally spoke to someone higher up at 5.45pm tonight.
She told me that the computer calculation was correct, and due to receiving pensioner premium, we not only loose the the enhanced disability premium( in the ESA legislation) of £24.10, we ALSO LOOSE the couple SDP premium of £131.70.
This is how the computer system is presently programmed. I explained that nowhere in the ESA legislation or on government websites explaining disability premiums, does it state that receiving the pensioner premium precludes the claimant getting any disability premiums whatsoever.
She agreed that there may be a problem, and she would speak to her manager on Monday and ring me back Monday pm. However, she also said that this may have to go much higher than her manager if, as it seems, the computer has not been updated to take into account the new rules regarding Mixed Age couples, as my wife will be among the first who was unable to claim pension credit .
This actually seems to have the probability of becoming a disaster, as more Mixed Age couples fall foul of these present rules.
I will let you know when I hear something on Monday
Fred