Loss of SDA in migration to ESA?

Hold on..this is complex! Lol
Claim is in My Hubby's name I am appointee.
Hubby lost DLA Dec 2017 after PIP assessment. As a result Carers allowance paid to me stopped in Dec 2017. Now, this is where I am losing it.!!!! The Carers Allowance I got for hubby was means tested on our Income Support/ESA. which was reduce by the £62.20. I got paid by Carers Allowance on a Monday. Now that Hubby has lost DLA & I've lost Carers. Should the amount means tested be not added BACK to our ESA to be our Income Related amount?

Hubby was awarded SDA before he got DLA- back around 1999. This benefit stopped being available 2001 but existing claimants kept it. He was later awarded DLA. We were migrated to ESA Jan 2015, with no warning or consult. There was no difference to our money. I was awarded DLA in 2012 indefinitely as result of Breast cancer. Hubby was awarded carers allowance for me, but did not take the allowance as he had SDA. So he got it as underlying entitlement.
We are still getting joint carer PREMIUM for 8 weeks after CA was stopped.
Our ESA is £248.25 paid 2 weekly. This will drop to £213.55 pw
On my letter showing our benefits they have Carers Allowance for your partner £62.70. This is wrong as I am the partner & he did NOT get carers for me!
An anyone tell me..is this a fast one DWP/UKGOV has pulled when migrating folk to ESA...they lose SDA. Staff at DWP just keep saying I lose my premiums..but cannot tell me about SDA...they know nothing about it! Any Clarity would be very useful please!

I was a CAB volunteer but left for surgery just as ESA was coming in. Ooooh if only If I could just get a hold of the disability right handbook we used! I KNOW where they are messing up, but cannot get it through to them - no one is claiming Carers allowance yet they are reducing our ESA by the Carers amount. Seems they are in trouble already re ESA: www.disabilityrightsuk.org/news/2017/nov...illion-due-dwp-error